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Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Pure magnesium needed for making alloys can be obtained by electrolysis of molten magnesium chloride.

© International Baccalaureate Organization 2020.

Write the half-equations for the reactions occurring in this electrolysis.

Pure magnesium needed for making alloys can be obtained by electrolysis of molten magnesium chloride.

© International Baccalaureate Organization 2020.

Write the half-equations for the reactions occurring in this electrolysis.

Pure magnesium needed for making alloys can be obtained by electrolysis of molten magnesium chloride.

© International Baccalaureate Organization 2020.

Write the half-equations for the reactions occurring in this electrolysis.

Outline the two distinct phases of this composite.

Outline the two distinct phases of this composite.

Outline the two distinct phases of this composite.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Deduce the products of the hydrolysis of a non-substituted phospholipid, where ${\mathrm{R}}^1$ and ${\mathrm{R}}^2$ represent long alkyl chains.

Deduce the products of the hydrolysis of a non-substituted phospholipid, where ${\mathrm{R}}^1$ and ${\mathrm{R}}^2$ represent long alkyl chains.

Deduce the products of the hydrolysis of a non-substituted phospholipid, where ${\mathrm{R}}^1$ and ${\mathrm{R}}^2$ represent long alkyl chains.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

Calculate the BMF if a $120 \mathrm{kg}$ shark consumes $1000$ mackerel in one year. Each mackerel weighs $1 \mathrm{kg}$ on average. The ${\left[\mathrm{X}\right]}_{\mathrm{mackerel}}=0.3 \mathrm{\mu g} \mathrm{X}$ per $\mathrm{kg}$ body weight. Assume chemical $\mathrm{X}$ remains in the shark’s body for two years.

Calculate the BMF if a $120 \mathrm{kg}$ shark consumes $1000$ mackerel in one year. Each mackerel weighs $1 \mathrm{kg}$ on average. The ${\left[\mathrm{X}\right]}_{\mathrm{mackerel}}=0.3 \mathrm{\mu g} \mathrm{X}$ per $\mathrm{kg}$ body weight. Assume chemical $\mathrm{X}$ remains in the shark’s body for two years.

Calculate the BMF if a $120 \mathrm{kg}$ shark consumes $1000$ mackerel in one year. Each mackerel weighs $1 \mathrm{kg}$ on average. The ${\left[\mathrm{X}\right]}_{\mathrm{mackerel}}=0.3 \mathrm{\mu g} \mathrm{X}$ per $\mathrm{kg}$ body weight. Assume chemical $\mathrm{X}$ remains in the shark’s body for two years.

The diverse functions of biological molecules depend on their structure and shape.

Sucrose is a disaccharide formed in the reaction of glucose with fructose.
Identify the reaction type and the newly formed functional group that joins the monosaccharide units in the product.

The diverse functions of biological molecules depend on their structure and shape.

Sucrose is a disaccharide formed in the reaction of glucose with fructose.
Identify the reaction type and the newly formed functional group that joins the monosaccharide units in the product.

The diverse functions of biological molecules depend on their structure and shape.

Sucrose is a disaccharide formed in the reaction of glucose with fructose.
Identify the reaction type and the newly formed functional group that joins the monosaccharide units in the product.

A representation of a phospholipid bilayer cell membrane is shown:

© International Baccalaureate Organization 2020.

Identify the components of the phospholipid labelled A and B.

A representation of a phospholipid bilayer cell membrane is shown:

© International Baccalaureate Organization 2020.

Identify the components of the phospholipid labelled A and B.

A representation of a phospholipid bilayer cell membrane is shown:

© International Baccalaureate Organization 2020.

Identify the components of the phospholipid labelled A and B.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

A mixture of gasoline and ethanol is often used as a fuel. Suggest an advantage of such a mixture over the use of pure gasoline. Exclude any discussion of cost.

A mixture of gasoline and ethanol is often used as a fuel. Suggest an advantage of such a mixture over the use of pure gasoline. Exclude any discussion of cost.

A mixture of gasoline and ethanol is often used as a fuel. Suggest an advantage of such a mixture over the use of pure gasoline. Exclude any discussion of cost.

Comment on the risk of overdose when taking aspirin as an analgesic, referring to the following values, for a person weighing $70 \mathrm{kg}$:

Minimum therapeutic dose $=0.5 \mathrm{g}$

Estimated minimum lethal dose $=15 \mathrm{g}$

Comment on the risk of overdose when taking aspirin as an analgesic, referring to the following values, for a person weighing $70 \mathrm{kg}$:

Minimum therapeutic dose $=0.5 \mathrm{g}$

Estimated minimum lethal dose $=15 \mathrm{g}$

Comment on the risk of overdose when taking aspirin as an analgesic, referring to the following values, for a person weighing $70 \mathrm{kg}$:

Minimum therapeutic dose $=0.5 \mathrm{g}$

Estimated minimum lethal dose $=15 \mathrm{g}$

Deduce the structural formula of the by-product of this reaction.

Deduce the structural formula of the by-product of this reaction.

Deduce the structural formula of the by-product of this reaction.

Outline a green chemistry solution for problems generated by the use of organic solvents.

Outline a green chemistry solution for problems generated by the use of organic solvents.

Outline a green chemistry solution for problems generated by the use of organic solvents.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

Explain how zanamivir works as a preventative agent against flu viruses.

Explain how zanamivir works as a preventative agent against flu viruses.

Explain how zanamivir works as a preventative agent against flu viruses.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

Proteins are polymers of amino acids.

The mixture is composed of glycine, $\mathrm{Gly}$, and isoleucine, $\mathrm{Ile}$. Their structures can be found in section 33 of the data booklet.

Deduce, referring to relative affinities and ${\mathrm{R}}_{\mathrm{f}}$, the identity of A1.

Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Proteins are polymers of amino acids.

Glycine is one of the amino acids in the primary structure of hemoglobin.

State the type of bonding responsible for the α-helix in the secondary structure.

Outline the significance of the value of the Michaelis constant, $K_{\mathrm{m}}$.

Outline the significance of the value of the Michaelis constant, $K_{\mathrm{m}}$.

Outline the significance of the value of the Michaelis constant, $K_{\mathrm{m}}$.

Proteins are polymers of amino acids.

Explain why the affinity for oxygen of foetal hemoglobin differs from that of adult hemoglobin.

Proteins are polymers of amino acids.

Explain why the affinity for oxygen of foetal hemoglobin differs from that of adult hemoglobin.

Proteins are polymers of amino acids.

Explain why the affinity for oxygen of foetal hemoglobin differs from that of adult hemoglobin.

When combusted, all three fuels can release carbon dioxide, a greenhouse gas, as well as particulates. Contrast how carbon dioxide and particulates interact with sunlight.

When combusted, all three fuels can release carbon dioxide, a greenhouse gas, as well as particulates. Contrast how carbon dioxide and particulates interact with sunlight.

When combusted, all three fuels can release carbon dioxide, a greenhouse gas, as well as particulates. Contrast how carbon dioxide and particulates interact with sunlight.

Precipitation is one method used to treat waste water.

Phosphates, ${\mathrm{PO}}_4^{3-}$, in waste water can be removed by precipitation with magnesium ions. $K_{sp}$ of magnesium phosphate is $1.04\times {10}^{-24}$.

$3{\mathrm{Mg}}^{2+}\left(\mathrm{aq}\right)+2{{\mathrm{PO}}_4}^{3-}\left(\mathrm{aq}\right)\to {\mathrm{Mg}}_3\left({\mathrm{PO}}_4{)}_2\right(\mathrm{s})$

Calculate the maximum solubility of phosphate ions in a solution containing $0.0100 \mathrm{mol} {\mathrm{dm}}^{-3}$ magnesium ions.

Precipitation is one method used to treat waste water.

Phosphates, ${\mathrm{PO}}_4^{3-}$, in waste water can be removed by precipitation with magnesium ions. $K_{sp}$ of magnesium phosphate is $1.04\times {10}^{-24}$.

$3{\mathrm{Mg}}^{2+}\left(\mathrm{aq}\right)+2{{\mathrm{PO}}_4}^{3-}\left(\mathrm{aq}\right)\to {\mathrm{Mg}}_3\left({\mathrm{PO}}_4{)}_2\right(\mathrm{s})$

Calculate the maximum solubility of phosphate ions in a solution containing $0.0100 \mathrm{mol} {\mathrm{dm}}^{-3}$ magnesium ions.

Precipitation is one method used to treat waste water.

Phosphates, ${\mathrm{PO}}_4^{3-}$, in waste water can be removed by precipitation with magnesium ions. $K_{sp}$ of magnesium phosphate is $1.04\times {10}^{-24}$.

$3{\mathrm{Mg}}^{2+}\left(\mathrm{aq}\right)+2{{\mathrm{PO}}_4}^{3-}\left(\mathrm{aq}\right)\to {\mathrm{Mg}}_3\left({\mathrm{PO}}_4{)}_2\right(\mathrm{s})$

Calculate the maximum solubility of phosphate ions in a solution containing $0.0100 \mathrm{mol} {\mathrm{dm}}^{-3}$ magnesium ions.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Suggest a gas which should be continuously passed over the molten magnesium in the electrolytic cell.

Proteins are polymers of amino acids.

A paper chromatogram of two amino acids, A1 and A2, is obtained using a non-polar solvent.

© International Baccalaureate Organization 2020.

Determine the ${\mathrm{R}}_{\mathrm{f}}$ value of A1.

Proteins are polymers of amino acids.

A paper chromatogram of two amino acids, A1 and A2, is obtained using a non-polar solvent.

© International Baccalaureate Organization 2020.

Determine the ${\mathrm{R}}_{\mathrm{f}}$ value of A1.

Proteins are polymers of amino acids.

A paper chromatogram of two amino acids, A1 and A2, is obtained using a non-polar solvent.

© International Baccalaureate Organization 2020.

Determine the ${\mathrm{R}}_{\mathrm{f}}$ value of A1.

Determine the nuclear binding energy, in $\mathrm{J}$, of ${}_{238}\mathrm{U}$ using sections 2 and 4 of the data booklet.

The mass of the ${}_{238}\mathrm{U}$ nucleus is $238.050786 \mathrm{amu}$.

Determine the nuclear binding energy, in $\mathrm{J}$, of ${}_{238}\mathrm{U}$ using sections 2 and 4 of the data booklet.

The mass of the ${}_{238}\mathrm{U}$ nucleus is $238.050786 \mathrm{amu}$.

Determine the nuclear binding energy, in $\mathrm{J}$, of ${}_{238}\mathrm{U}$ using sections 2 and 4 of the data booklet.

The mass of the ${}_{238}\mathrm{U}$ nucleus is $238.050786 \mathrm{amu}$.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

The diverse functions of biological molecules depend on their structure and shape.

Deduce the straight chain structure of deoxyribose from its ring structure drawn in section 34 of the data booklet.

The half-life of ²³⁸U is $4.46\times {10}^9$ years. Calculate the mass of ²³⁸U that remains after $0.639 \mathrm{kg}$ has decayed for $2.23\times {10}^{10}$ years.

The half-life of ²³⁸U is $4.46\times {10}^9$ years. Calculate the mass of ²³⁸U that remains after $0.639 \mathrm{kg}$ has decayed for $2.23\times {10}^{10}$ years.

The half-life of ²³⁸U is $4.46\times {10}^9$ years. Calculate the mass of ²³⁸U that remains after $0.639 \mathrm{kg}$ has decayed for $2.23\times {10}^{10}$ years.

Deduce the nuclear equation for the decay of uranium-238 to thorium-234.

Deduce the nuclear equation for the decay of uranium-238 to thorium-234.

Deduce the nuclear equation for the decay of uranium-238 to thorium-234.

Determine the relative rate of effusion of methane ($M_{\mathrm{r}}=16.05$) to carbon dioxide ($M_{\mathrm{r}}=44.01$), under the same conditions of temperature and pressure. Use section 1 of the data booklet.

Determine the relative rate of effusion of methane ($M_{\mathrm{r}}=16.05$) to carbon dioxide ($M_{\mathrm{r}}=44.01$), under the same conditions of temperature and pressure. Use section 1 of the data booklet.

Determine the relative rate of effusion of methane ($M_{\mathrm{r}}=16.05$) to carbon dioxide ($M_{\mathrm{r}}=44.01$), under the same conditions of temperature and pressure. Use section 1 of the data booklet.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

The solubility of aspirin is increased by converting it to an ionic form. Draw the structure of the ionic form of aspirin.

Describe the proper disposal of low-level radioactive waste in hospitals.

Describe the proper disposal of low-level radioactive waste in hospitals.

Describe the proper disposal of low-level radioactive waste in hospitals.

State the type of radiation technetium-99m emits.

State the type of radiation technetium-99m emits.

State the type of radiation technetium-99m emits.

Technetium-99m has a half-life of $6.03$ hours. Calculate the amount of $1.00\times {10}^{-11} \mathrm{mol}$ of technetium-99m remaining after $48.0$ hours.

Technetium-99m has a half-life of $6.03$ hours. Calculate the amount of $1.00\times {10}^{-11} \mathrm{mol}$ of technetium-99m remaining after $48.0$ hours.

Technetium-99m has a half-life of $6.03$ hours. Calculate the amount of $1.00\times {10}^{-11} \mathrm{mol}$ of technetium-99m remaining after $48.0$ hours.

Explain how zanamivir works as a preventative agent against flu viruses.

Explain how zanamivir works as a preventative agent against flu viruses.

Explain how zanamivir works as a preventative agent against flu viruses.

Outline the composition of an alloy and a composite.

Outline the composition of an alloy and a composite.

Outline the composition of an alloy and a composite.

State equations for the formation of iron nanoparticles and carbon atoms from Fe(CO)₅ in the HIPCO process.

State equations for the formation of iron nanoparticles and carbon atoms from Fe(CO)₅ in the HIPCO process.

State equations for the formation of iron nanoparticles and carbon atoms from Fe(CO)₅ in the HIPCO process.

Calculate the loss in mass, in kg, and the energy released, in J, when 0.00100 mol of ²²⁸Ac decays, each atom losing an electron. Use section 2 of the data booklet and E = mc².

²²⁸Ac → ${}_{-1}^0\text{e}$ + ²²⁸Th

Calculate the loss in mass, in kg, and the energy released, in J, when 0.00100 mol of ²²⁸Ac decays, each atom losing an electron. Use section 2 of the data booklet and E = mc².

²²⁸Ac → ${}_{-1}^0\text{e}$ + ²²⁸Th

Calculate the loss in mass, in kg, and the energy released, in J, when 0.00100 mol of ²²⁸Ac decays, each atom losing an electron. Use section 2 of the data booklet and E = mc².

²²⁸Ac → ${}_{-1}^0\text{e}$ + ²²⁸Th

Outline the importance of linoleic acid for human health.

Outline the importance of linoleic acid for human health.

Outline the importance of linoleic acid for human health.

The solubility product, K_sp , of cadmium sulfide, CdS, is 8.0 × 10^–27. Determine the concentration of cadmium ions in 1.0 dm³ of a saturated solution of cadmium sulfide to which 0.10 mol of solid sodium sulfide has been added, stating any assumption you make.

The solubility product, K_sp , of cadmium sulfide, CdS, is 8.0 × 10^–27. Determine the concentration of cadmium ions in 1.0 dm³ of a saturated solution of cadmium sulfide to which 0.10 mol of solid sodium sulfide has been added, stating any assumption you make.

The solubility product, K_sp , of cadmium sulfide, CdS, is 8.0 × 10^–27. Determine the concentration of cadmium ions in 1.0 dm³ of a saturated solution of cadmium sulfide to which 0.10 mol of solid sodium sulfide has been added, stating any assumption you make.

Determine the value of the Michaelis constant, K_m, by annotating the graph.

Determine the value of the Michaelis constant, K_m, by annotating the graph.

Determine the value of the Michaelis constant, K_m, by annotating the graph.

The stability of DNA is due to interactions of its hydrophilic and hydrophobic components.

Outline the interactions of the phosphate groups in DNA with water and with surrounding proteins (histones).

The stability of DNA is due to interactions of its hydrophilic and hydrophobic components.

Outline the interactions of the phosphate groups in DNA with water and with surrounding proteins (histones).

Explain the low environmental impact of most medical nuclear waste.

Explain the low environmental impact of most medical nuclear waste.

Explain the low environmental impact of most medical nuclear waste.

Explain the role of the chiral auxiliary in the synthesis of Taxol.

Explain the role of the chiral auxiliary in the synthesis of Taxol.

Explain the role of the chiral auxiliary in the synthesis of Taxol.

One of the two infrared (IR) spectra is that of polyethene and the other of polytetrafluoroethene (PTFE).

Deduce, with a reason, which spectrum is that of PTFE. Infrared data is given in section 26 of the data booklet.

One of the two infrared (IR) spectra is that of polyethene and the other of polytetrafluoroethene (PTFE).

Deduce, with a reason, which spectrum is that of PTFE. Infrared data is given in section 26 of the data booklet.

One of the two infrared (IR) spectra is that of polyethene and the other of polytetrafluoroethene (PTFE).

Deduce, with a reason, which spectrum is that of PTFE. Infrared data is given in section 26 of the data booklet.

Explain how the inclusion of carbohydrates in plastics makes them biodegradable.

Explain how the inclusion of carbohydrates in plastics makes them biodegradable.

Explain how the inclusion of carbohydrates in plastics makes them biodegradable.

A typical wood has a specific energy of 17 × 10³ kJ kg^–1. Comment on the usefulness of octane and wood for powering a moving vehicle, using your answer to (a).

If you did not work out an answer for (a), use 45 × 10³ kJ kg^–1 but this is not the correct answer.

A typical wood has a specific energy of 17 × 10³ kJ kg^–1. Comment on the usefulness of octane and wood for powering a moving vehicle, using your answer to (a).

If you did not work out an answer for (a), use 45 × 10³ kJ kg^–1 but this is not the correct answer.

A typical wood has a specific energy of 17 × 10³ kJ kg^–1. Comment on the usefulness of octane and wood for powering a moving vehicle, using your answer to (a).

If you did not work out an answer for (a), use 45 × 10³ kJ kg^–1 but this is not the correct answer.

Calculate the total number of cobalt atoms within its unit cell.

Calculate the total number of cobalt atoms within its unit cell.

Calculate the total number of cobalt atoms within its unit cell.

Determine the energy released, in J, by 0.00100 mol of ²²⁸Ac over the course of 18 hours.

Determine the energy released, in J, by 0.00100 mol of ²²⁸Ac over the course of 18 hours.

Determine the energy released, in J, by 0.00100 mol of ²²⁸Ac over the course of 18 hours.

Outline one advantage and one disadvantage of the methanol cell (DMFC) compared with a hydrogen-oxygen fuel cell.

Outline one advantage and one disadvantage of the methanol cell (DMFC) compared with a hydrogen-oxygen fuel cell.

Outline one advantage and one disadvantage of the methanol cell (DMFC) compared with a hydrogen-oxygen fuel cell.

Draw a curve on the graph above showing the effect of the presence of the malonate ion inhibitor on the rate of reaction.

Draw a curve on the graph above showing the effect of the presence of the malonate ion inhibitor on the rate of reaction.

Draw a curve on the graph above showing the effect of the presence of the malonate ion inhibitor on the rate of reaction.

State the half-equation for the reduction of molecular oxygen to water in acidic conditions.

State the half-equation for the reduction of molecular oxygen to water in acidic conditions.

State the half-equation for the reduction of molecular oxygen to water in acidic conditions.

The natural absorption of light by chlorophyll has been copied by those developing dye-sensitized solar cells (DSSCs). Outline how a DSSC works.

The natural absorption of light by chlorophyll has been copied by those developing dye-sensitized solar cells (DSSCs). Outline how a DSSC works.

The natural absorption of light by chlorophyll has been copied by those developing dye-sensitized solar cells (DSSCs). Outline how a DSSC works.

Deduce the half-equations and the overall equation for the reactions taking place in a direct methanol fuel cell (DMFC) under acidic conditions.

Deduce the half-equations and the overall equation for the reactions taking place in a direct methanol fuel cell (DMFC) under acidic conditions.

Deduce the half-equations and the overall equation for the reactions taking place in a direct methanol fuel cell (DMFC) under acidic conditions.

The half-life of lutetium-177 is 6.73 days. Determine the percentage of a sample of lutetium-177 remaining after 14.0 days.

The half-life of lutetium-177 is 6.73 days. Determine the percentage of a sample of lutetium-177 remaining after 14.0 days.

The half-life of lutetium-177 is 6.73 days. Determine the percentage of a sample of lutetium-177 remaining after 14.0 days.

Explain why Type 2 superconductors are generally more useful than Type 1.

Explain why Type 2 superconductors are generally more useful than Type 1.

Explain why Type 2 superconductors are generally more useful than Type 1.

Identify the type of intermolecular bonding that is responsible for Kevlar^®’s strength.

Identify the type of intermolecular bonding that is responsible for Kevlar^®’s strength.

Identify the type of intermolecular bonding that is responsible for Kevlar^®’s strength.

The atomic radius, r, of cobalt is 1.18 × 10^–8 cm. Determine the edge length, in cm, of the unit cell, a, using the second diagram.

The atomic radius, r, of cobalt is 1.18 × 10^–8 cm. Determine the edge length, in cm, of the unit cell, a, using the second diagram.

The atomic radius, r, of cobalt is 1.18 × 10^–8 cm. Determine the edge length, in cm, of the unit cell, a, using the second diagram.

Determine a value for the density of cobalt, in g cm^–3, using data from sections 2 and 6 of the data booklet and your answers from (a) and (b) (i).

If you did not obtain an answer to (b) (i), use 3.00 × 10^–8 cm but this is not the correct answer.

Determine a value for the density of cobalt, in g cm^–3, using data from sections 2 and 6 of the data booklet and your answers from (a) and (b) (i).

If you did not obtain an answer to (b) (i), use 3.00 × 10^–8 cm but this is not the correct answer.

Determine a value for the density of cobalt, in g cm^–3, using data from sections 2 and 6 of the data booklet and your answers from (a) and (b) (i).

If you did not obtain an answer to (b) (i), use 3.00 × 10^–8 cm but this is not the correct answer.

Deduce which spectrum belongs to paracetamol, giving two reasons for your choice. Use section 26 of the data booklet.

Deduce which spectrum belongs to paracetamol, giving two reasons for your choice. Use section 26 of the data booklet.

Deduce which spectrum belongs to paracetamol, giving two reasons for your choice. Use section 26 of the data booklet.

Explain why opiates are addictive.

Explain why opiates are addictive.

Explain why opiates are addictive.

Outline the difference between the therapeutic index in animal studies and the therapeutic index in humans.

Outline the difference between the therapeutic index in animal studies and the therapeutic index in humans.

Outline the difference between the therapeutic index in animal studies and the therapeutic index in humans.

Explain, at the molecular level, why vitamin D is soluble in fats. Use section 35 of the data booklet.

Explain, at the molecular level, why vitamin D is soluble in fats. Use section 35 of the data booklet.

Explain, at the molecular level, why vitamin D is soluble in fats. Use section 35 of the data booklet.

“Knocking” in an automobile (car) engine can be prevented by increasing the octane number of the fuel. Explain, including an equation with structural formulas, how heptane, C₇H₁₆, could be chemically converted to increase its octane number.

“Knocking” in an automobile (car) engine can be prevented by increasing the octane number of the fuel. Explain, including an equation with structural formulas, how heptane, C₇H₁₆, could be chemically converted to increase its octane number.

“Knocking” in an automobile (car) engine can be prevented by increasing the octane number of the fuel. Explain, including an equation with structural formulas, how heptane, C₇H₁₆, could be chemically converted to increase its octane number.

Radioisotopes are used to diagnose and treat various diseases. Explain the low environmental impact of most medical nuclear waste.

Radioisotopes are used to diagnose and treat various diseases. Explain the low environmental impact of most medical nuclear waste.

Explain how Inductively Coupled Plasma (ICP) Spectroscopy could be used to determine the concentration of mercury in a sample of dental filling.

Explain how Inductively Coupled Plasma (ICP) Spectroscopy could be used to determine the concentration of mercury in a sample of dental filling.

Explain how Inductively Coupled Plasma (ICP) Spectroscopy could be used to determine the concentration of mercury in a sample of dental filling.

Catalysts can take many forms and are used in many industrial processes.

Suggest two reasons why it might be worth using a more expensive catalyst to increase the rate of a reaction.

Catalysts can take many forms and are used in many industrial processes.

Suggest two reasons why it might be worth using a more expensive catalyst to increase the rate of a reaction.

Describe what is meant by a condensation reaction.

Describe what is meant by a condensation reaction.

Describe what is meant by a condensation reaction.

Outline two properties a substance should have to be used as liquid-crystal in a liquid-crystal display.

Outline two properties a substance should have to be used as liquid-crystal in a liquid-crystal display.

Outline two properties a substance should have to be used as liquid-crystal in a liquid-crystal display.

Many plastics used to be incinerated. Deduce an equation for the complete combustion of two repeating units of PVC, (–C₂H₃Cl–)₂.

Many plastics used to be incinerated. Deduce an equation for the complete combustion of two repeating units of PVC, (–C₂H₃Cl–)₂.

Many plastics used to be incinerated. Deduce an equation for the complete combustion of two repeating units of PVC, (–C₂H₃Cl–)₂.

State the names of two functional groups that both compounds contain, using section 37 of the data booklet.

State the names of two functional groups that both compounds contain, using section 37 of the data booklet.

State the names of two functional groups that both compounds contain, using section 37 of the data booklet.

The pH is maintained in different fluids in the body by the use of buffers.

Calculate the pH of a buffer solution of 0.0200 mol dm^–3 carbonic acid, H₂CO₃, and 0.400 mol dm^–3 sodium hydrogen carbonate, NaHCO₃. The pK_a of carbonic acid is 6.35.

The pH is maintained in different fluids in the body by the use of buffers.

Calculate the pH of a buffer solution of 0.0200 mol dm^–3 carbonic acid, H₂CO₃, and 0.400 mol dm^–3 sodium hydrogen carbonate, NaHCO₃. The pK_a of carbonic acid is 6.35.

The pH is maintained in different fluids in the body by the use of buffers.

Calculate the pH of a buffer solution of 0.0200 mol dm^–3 carbonic acid, H₂CO₃, and 0.400 mol dm^–3 sodium hydrogen carbonate, NaHCO₃. The pK_a of carbonic acid is 6.35.

Many like to refer to our “carbon footprint”. Outline one difficulty in quantifying such a concept.

Many like to refer to our “carbon footprint”. Outline one difficulty in quantifying such a concept.

Many like to refer to our “carbon footprint”. Outline one difficulty in quantifying such a concept.

The amount of ²²⁸Ac in a sample decreases to one eighth $\left(\frac{1}{8}\right)$ of its original value in about 18 hours due to β-decay. Estimate the half-life of ²²⁸Ac.

The amount of ²²⁸Ac in a sample decreases to one eighth $\left(\frac{1}{8}\right)$ of its original value in about 18 hours due to β-decay. Estimate the half-life of ²²⁸Ac.

The amount of ²²⁸Ac in a sample decreases to one eighth $\left(\frac{1}{8}\right)$ of its original value in about 18 hours due to β-decay. Estimate the half-life of ²²⁸Ac.

Calculate the volume of iodine solution used to reach the end-point. 

Calculate the volume of iodine solution used to reach the end-point. 

Calculate the volume of iodine solution used to reach the end-point. 

Calculate the specific energy of octane, C₈H₁₈, in kJ kg^–1 using sections 1, 6 and 13 of the data booklet.

Calculate the specific energy of octane, C₈H₁₈, in kJ kg^–1 using sections 1, 6 and 13 of the data booklet.

Calculate the specific energy of octane, C₈H₁₈, in kJ kg^–1 using sections 1, 6 and 13 of the data booklet.

Climate change or global warming is a consequence of increased levels of carbon dioxide in the atmosphere. Explain how the greenhouse effect warms the surface of the earth.

Climate change or global warming is a consequence of increased levels of carbon dioxide in the atmosphere. Explain how the greenhouse effect warms the surface of the earth.

Climate change or global warming is a consequence of increased levels of carbon dioxide in the atmosphere. Explain how the greenhouse effect warms the surface of the earth.

Compare and contrast fission and fusion in terms of binding energy and the types of nuclei involved.

Compare and contrast fission and fusion in terms of binding energy and the types of nuclei involved.

Compare and contrast fission and fusion in terms of binding energy and the types of nuclei involved.

Suggest two advantages that fusion has over fission.

Suggest two advantages that fusion has over fission.

Suggest two advantages that fusion has over fission.

The strong analgesics morphine and codeine are opiates. Outline how codeine can be synthesized from morphine. The structures of morphine and codeine are in section 37 of the data booklet.

The strong analgesics morphine and codeine are opiates. Outline how codeine can be synthesized from morphine. The structures of morphine and codeine are in section 37 of the data booklet.

The strong analgesics morphine and codeine are opiates. Outline how codeine can be synthesized from morphine. The structures of morphine and codeine are in section 37 of the data booklet.

Explain how ranitidine (Zantac) reduces stomach acid production.

Explain how ranitidine (Zantac) reduces stomach acid production.

Explain how ranitidine (Zantac) reduces stomach acid production.

Describe how the structures of LDPE and HDPE affect one mechanical property of the plastics.

Describe how the structures of LDPE and HDPE affect one mechanical property of the plastics.

Describe how the structures of LDPE and HDPE affect one mechanical property of the plastics.

Draw the structure of the monomer from which nylon-6 is produced by a condensation reaction.

Draw the structure of the monomer from which nylon-6 is produced by a condensation reaction.

Draw the structure of the monomer from which nylon-6 is produced by a condensation reaction.

Dye-sensitized solar cells, DSSCs, use a dye to absorb the sunlight. State two advantages that DSSCs have over traditional silicon based photovoltaic cells.

Dye-sensitized solar cells, DSSCs, use a dye to absorb the sunlight. State two advantages that DSSCs have over traditional silicon based photovoltaic cells.

Dye-sensitized solar cells, DSSCs, use a dye to absorb the sunlight. State two advantages that DSSCs have over traditional silicon based photovoltaic cells.

Deduce the number of atoms per unit cell in vanadium.

Deduce the number of atoms per unit cell in vanadium.

Deduce the number of atoms per unit cell in vanadium.

Vanadium and other transition metals can interfere with cell metabolism.

State and explain one process, other than by creating free radicals, by which transition metals interfere with cell metabolism.

Vanadium and other transition metals can interfere with cell metabolism.

State and explain one process, other than by creating free radicals, by which transition metals interfere with cell metabolism.

Vanadium and other transition metals can interfere with cell metabolism.

State and explain one process, other than by creating free radicals, by which transition metals interfere with cell metabolism.

Taxol was originally obtained from the bark of the Pacific yew tree.

Outline how Green Chemistry has improved the process of obtaining Taxol.

Taxol was originally obtained from the bark of the Pacific yew tree.

Outline how Green Chemistry has improved the process of obtaining Taxol.

The diagram illustrates the crystal structure of aluminium metal with the unit cell indicated. Outline the significance of the unit cell.

The diagram illustrates the crystal structure of aluminium metal with the unit cell indicated. Outline the significance of the unit cell.

The diagram illustrates the crystal structure of aluminium metal with the unit cell indicated. Outline the significance of the unit cell.

Outline why anthocyanins are coloured.

Outline why anthocyanins are coloured.

Outline why anthocyanins are coloured.

Explain why the blue colour of a quinoidal base changes to the red colour of a flavylium cation as pH decreases.

Explain why the blue colour of a quinoidal base changes to the red colour of a flavylium cation as pH decreases.

Explain why the blue colour of a quinoidal base changes to the red colour of a flavylium cation as pH decreases.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

Complete the half-equations on the diagram and identify the species moving between the electrodes.

Complete the half-equations on the diagram and identify the species moving between the electrodes.

Complete the half-equations on the diagram and identify the species moving between the electrodes.

State the factor that limits the maximum current that can be drawn from this cell and how electrodes are designed to maximize the current.

State the factor that limits the maximum current that can be drawn from this cell and how electrodes are designed to maximize the current.

State the factor that limits the maximum current that can be drawn from this cell and how electrodes are designed to maximize the current.

Explain how the proportion of ²³⁵U in natural uranium is increased.

Explain how the proportion of ²³⁵U in natural uranium is increased.

Explain how the proportion of ²³⁵U in natural uranium is increased.

Early photovoltaic cells were based on silicon containing traces of other elements. State the type of semiconductor produced by doping silicon with indium, In, giving a reason that refers to its electronic structure.

Early photovoltaic cells were based on silicon containing traces of other elements. State the type of semiconductor produced by doping silicon with indium, In, giving a reason that refers to its electronic structure.

Early photovoltaic cells were based on silicon containing traces of other elements. State the type of semiconductor produced by doping silicon with indium, In, giving a reason that refers to its electronic structure.

The structure of two dyes used in DSSCs are shown.

Predict, giving a reason, which dye will absorb light of longer wavelength.

The structure of two dyes used in DSSCs are shown.

Predict, giving a reason, which dye will absorb light of longer wavelength.

The structure of two dyes used in DSSCs are shown.

Predict, giving a reason, which dye will absorb light of longer wavelength.

Many drugs are chiral. Explain how a polarimeter can be used to determine the relative proportion of two enantiomers.

Many drugs are chiral. Explain how a polarimeter can be used to determine the relative proportion of two enantiomers.

Many drugs are chiral. Explain how a polarimeter can be used to determine the relative proportion of two enantiomers.

Describe how ionizing radiation destroys cancer cells.

Describe how ionizing radiation destroys cancer cells.

Describe how ionizing radiation destroys cancer cells.

Outline how Targeted Alpha Therapy (TAT) is used for treating cancers that have spread throughout the body.

Outline how Targeted Alpha Therapy (TAT) is used for treating cancers that have spread throughout the body.

Outline how Targeted Alpha Therapy (TAT) is used for treating cancers that have spread throughout the body.

Hexane and propanone have vapour pressures of 17 kPa and 24 kPa respectively at 20 °C.

Calculate the vapour pressure, in kPa, at 20 °C of a mixture containing 60% hexane and 40% propanone by mole fraction, using Raoult’s law and assuming the mixture is ideal.

Hexane and propanone have vapour pressures of 17 kPa and 24 kPa respectively at 20 °C.

Calculate the vapour pressure, in kPa, at 20 °C of a mixture containing 60% hexane and 40% propanone by mole fraction, using Raoult’s law and assuming the mixture is ideal.

Hexane and propanone have vapour pressures of 17 kPa and 24 kPa respectively at 20 °C.

Calculate the vapour pressure, in kPa, at 20 °C of a mixture containing 60% hexane and 40% propanone by mole fraction, using Raoult’s law and assuming the mixture is ideal.

Explain how hexane and propanone may be separated by fractional distillation.

Explain how hexane and propanone may be separated by fractional distillation.

Explain how hexane and propanone may be separated by fractional distillation.

The concentration of aluminium in drinking water can be reduced by precipitating aluminium hydroxide. Calculate the maximum concentration of aluminium ions in water of pH 7 at 298 K. Solubility product of aluminium hydroxide = 3.3 × 10⁻³⁴ at 298 K.

The concentration of aluminium in drinking water can be reduced by precipitating aluminium hydroxide. Calculate the maximum concentration of aluminium ions in water of pH 7 at 298 K. Solubility product of aluminium hydroxide = 3.3 × 10⁻³⁴ at 298 K.

The concentration of aluminium in drinking water can be reduced by precipitating aluminium hydroxide. Calculate the maximum concentration of aluminium ions in water of pH 7 at 298 K. Solubility product of aluminium hydroxide = 3.3 × 10⁻³⁴ at 298 K.

Hemoglobin’s oxygen dissociation curve is shown at a given temperature. Sketch the curve on the graph at a higher temperature.

Hemoglobin’s oxygen dissociation curve is shown at a given temperature. Sketch the curve on the graph at a higher temperature.

Hemoglobin’s oxygen dissociation curve is shown at a given temperature. Sketch the curve on the graph at a higher temperature.

Fuel cells have a higher thermodynamic efficiency than octane. The following table gives some information on a direct methanol fuel cell.

Determine the thermodynamic efficiency of a methanol fuel cell operating at 0.576 V.

Use sections 1 and 2 of the data booklet.

Fuel cells have a higher thermodynamic efficiency than octane. The following table gives some information on a direct methanol fuel cell.

Determine the thermodynamic efficiency of a methanol fuel cell operating at 0.576 V.

Use sections 1 and 2 of the data booklet.

Fuel cells have a higher thermodynamic efficiency than octane. The following table gives some information on a direct methanol fuel cell.

Determine the thermodynamic efficiency of a methanol fuel cell operating at 0.576 V.

Use sections 1 and 2 of the data booklet.

The half-life of phosphorus-32 is 14.3 days. Calculate the mass, in g, of ³²P remaining after 57.2 days if the initial sample contains 2.63 × 10⁻⁸ mol. Use table 1 of the data booklet and M_r = 31.97 g mol⁻¹.

The half-life of phosphorus-32 is 14.3 days. Calculate the mass, in g, of ³²P remaining after 57.2 days if the initial sample contains 2.63 × 10⁻⁸ mol. Use table 1 of the data booklet and M_r = 31.97 g mol⁻¹.

The half-life of phosphorus-32 is 14.3 days. Calculate the mass, in g, of ³²P remaining after 57.2 days if the initial sample contains 2.63 × 10⁻⁸ mol. Use table 1 of the data booklet and M_r = 31.97 g mol⁻¹.

When X-rays of wavelength 0.154 nm are directed at a crystal of aluminium, the first order diffraction pattern is observed at 18°. Determine the separation of layers of aluminium atoms in the crystal, in m, using section 1 of the data booklet.

When X-rays of wavelength 0.154 nm are directed at a crystal of aluminium, the first order diffraction pattern is observed at 18°. Determine the separation of layers of aluminium atoms in the crystal, in m, using section 1 of the data booklet.

When X-rays of wavelength 0.154 nm are directed at a crystal of aluminium, the first order diffraction pattern is observed at 18°. Determine the separation of layers of aluminium atoms in the crystal, in m, using section 1 of the data booklet.

Describe how DNA determines the primary structure of a protein such as insulin.

Describe how DNA determines the primary structure of a protein such as insulin.

Describe how DNA determines the primary structure of a protein such as insulin.

Outline why cellulose fibres are strong.

Outline why cellulose fibres are strong.

Outline why cellulose fibres are strong.

Distinguish between the manufacture of polyester and polyethene.

Distinguish between the manufacture of polyester and polyethene.

Distinguish between the manufacture of polyester and polyethene.

Outline two differences between normal hemoglobin and foetal hemoglobin.

Outline two differences between normal hemoglobin and foetal hemoglobin.

Outline two differences between normal hemoglobin and foetal hemoglobin.

Draw the Lewis (electron dot) structure for an appropriate doping element in the box in the centre identifying the type of semiconductor formed.

Draw the Lewis (electron dot) structure for an appropriate doping element in the box in the centre identifying the type of semiconductor formed.

Draw the Lewis (electron dot) structure for an appropriate doping element in the box in the centre identifying the type of semiconductor formed.

Outline why complex B absorbs light of longer wavelength than complex A.

Outline why complex B absorbs light of longer wavelength than complex A.

Outline why complex B absorbs light of longer wavelength than complex A.

Explain the targeted alpha therapy (TAT) technique and why it is useful.

Explain the targeted alpha therapy (TAT) technique and why it is useful.

Explain the targeted alpha therapy (TAT) technique and why it is useful.

Deduce what the shape of the graph indicates about aluminium.

Deduce what the shape of the graph indicates about aluminium.

Deduce what the shape of the graph indicates about aluminium.

Outline the significance of the value of the Michaelis constant, K_m.

Outline the significance of the value of the Michaelis constant, K_m.

Outline the significance of the value of the Michaelis constant, K_m.

Calculate the average mass, in g, of a vanadium atom by using sections 2 and 6 of the data booklet.

Calculate the average mass, in g, of a vanadium atom by using sections 2 and 6 of the data booklet.

Calculate the average mass, in g, of a vanadium atom by using sections 2 and 6 of the data booklet.

MWCNT are very small in size and can greatly increase switching speeds in a liquid crystal allowing the liquid crystal to change orientation quickly.

Discuss two other properties a substance should have to be suitable for use in liquid crystal displays.

MWCNT are very small in size and can greatly increase switching speeds in a liquid crystal allowing the liquid crystal to change orientation quickly.

Discuss two other properties a substance should have to be suitable for use in liquid crystal displays.

MWCNT are very small in size and can greatly increase switching speeds in a liquid crystal allowing the liquid crystal to change orientation quickly.

Discuss two other properties a substance should have to be suitable for use in liquid crystal displays.

Calculate the pH of a buffer system with a concentration of 1.25 × 10⁻³ mol dm⁻³ carbonic acid and 2.50 × 10⁻² mol dm⁻³ sodium hydrogen carbonate. Use section 1 of the data booklet.

pK_a (carbonic acid) = 6.36

Calculate the pH of a buffer system with a concentration of 1.25 × 10⁻³ mol dm⁻³ carbonic acid and 2.50 × 10⁻² mol dm⁻³ sodium hydrogen carbonate. Use section 1 of the data booklet.

pK_a (carbonic acid) = 6.36

Calculate the pH of a buffer system with a concentration of 1.25 × 10⁻³ mol dm⁻³ carbonic acid and 2.50 × 10⁻² mol dm⁻³ sodium hydrogen carbonate. Use section 1 of the data booklet.

pK_a (carbonic acid) = 6.36

DNA is a biopolymer made up of nucleotides. List two components of a nucleotide.

DNA is a biopolymer made up of nucleotides. List two components of a nucleotide.

Explain with reference to the binding site on the enzyme how a non-competitive inhibitor lowers the value of V_max.

Explain with reference to the binding site on the enzyme how a non-competitive inhibitor lowers the value of V_max.

Explain with reference to the binding site on the enzyme how a non-competitive inhibitor lowers the value of V_max.

Calculate the expected first order diffraction pattern angle, in degrees, if x-rays of wavelength 150 pm are directed at a crystal of vanadium. Assume the edge length of the crystal to be the same as separation of layers of vanadium atoms found by x-ray diffraction. Use section 1 of the data booklet.

Calculate the expected first order diffraction pattern angle, in degrees, if x-rays of wavelength 150 pm are directed at a crystal of vanadium. Assume the edge length of the crystal to be the same as separation of layers of vanadium atoms found by x-ray diffraction. Use section 1 of the data booklet.

Calculate the expected first order diffraction pattern angle, in degrees, if x-rays of wavelength 150 pm are directed at a crystal of vanadium. Assume the edge length of the crystal to be the same as separation of layers of vanadium atoms found by x-ray diffraction. Use section 1 of the data booklet.

Determine the volume, in cm³, of a vanadium unit cell.

Determine the volume, in cm³, of a vanadium unit cell.

Determine the volume, in cm³, of a vanadium unit cell.

Explain how the structure of vitamin A is important to vision using section 35 of the data booklet.

Explain how the structure of vitamin A is important to vision using section 35 of the data booklet.

Explain how the structure of vitamin A is important to vision using section 35 of the data booklet.

Calculate the relative rate of effusion of ²³⁵UF₆(g) to ²³⁸UF₆(g) using sections 1 and 6 of the data booklet.

Calculate the relative rate of effusion of ²³⁵UF₆(g) to ²³⁸UF₆(g) using sections 1 and 6 of the data booklet.

Calculate the relative rate of effusion of ²³⁵UF₆(g) to ²³⁸UF₆(g) using sections 1 and 6 of the data booklet.

State the feature of the molecules responsible for the absorption of light.

State the feature of the molecules responsible for the absorption of light.

State the feature of the molecules responsible for the absorption of light.

Phosphorous-32 undergoes beta decay. Formulate a balanced nuclear equation for this process.

Phosphorous-32 undergoes beta decay. Formulate a balanced nuclear equation for this process.

Phosphorous-32 undergoes beta decay. Formulate a balanced nuclear equation for this process.

Fuel cells use an electrochemical process to determine the concentration of ethanol.

Formulate the overall equation for this process.

Fuel cells use an electrochemical process to determine the concentration of ethanol.

Formulate the overall equation for this process.

Fuel cells use an electrochemical process to determine the concentration of ethanol.

Formulate the overall equation for this process.

Outline why the resistance of aluminium increases above 1.2 K.

Outline why the resistance of aluminium increases above 1.2 K.

Outline why the resistance of aluminium increases above 1.2 K.

Determine the density, in g cm⁻³, of vanadium by using your answers to (a)(i), (a)(iii) and (a)(iv).

Determine the density, in g cm⁻³, of vanadium by using your answers to (a)(i), (a)(iii) and (a)(iv).

Determine the density, in g cm⁻³, of vanadium by using your answers to (a)(i), (a)(iii) and (a)(iv).

Explain, based on molecular structure and bonding, why diffusion or centrifuging can be used for enrichment of UF₆ but not UO₂.

Explain, based on molecular structure and bonding, why diffusion or centrifuging can be used for enrichment of UF₆ but not UO₂.

Explain, based on molecular structure and bonding, why diffusion or centrifuging can be used for enrichment of UF₆ but not UO₂.

Vanadium(IV) ions can create free radicals by a Fenton reaction.

Deduce the equation for the reaction of V⁴⁺ with hydrogen peroxide.

Vanadium(IV) ions can create free radicals by a Fenton reaction.

Deduce the equation for the reaction of V⁴⁺ with hydrogen peroxide.

Vanadium(IV) ions can create free radicals by a Fenton reaction.

Deduce the equation for the reaction of V⁴⁺ with hydrogen peroxide.

Draw the structures of the main form of glycine in buffer solutions of pH 1.0 and 6.0.

The pK_a of glycine is 2.34.

Draw the structures of the main form of glycine in buffer solutions of pH 1.0 and 6.0.

The pK_a of glycine is 2.34.

Draw the structures of the main form of glycine in buffer solutions of pH 1.0 and 6.0.

The pK_a of glycine is 2.34.

Predict the chemical shifts and integration for each signal in the ¹H NMR spectrum for ethanol using section 27 of the data booklet.

Predict the chemical shifts and integration for each signal in the ¹H NMR spectrum for ethanol using section 27 of the data booklet.

Predict the chemical shifts and integration for each signal in the ¹H NMR spectrum for ethanol using section 27 of the data booklet.

Discuss, in terms of its structure, why an aluminium saucepan is impermeable to water.

Discuss, in terms of its structure, why an aluminium saucepan is impermeable to water.

Discuss, in terms of its structure, why an aluminium saucepan is impermeable to water.

State the name given to a material composed of two distinct solid phases.

State the name given to a material composed of two distinct solid phases.

State the name given to a material composed of two distinct solid phases.

State one physical property of HDPE that will be affected by the incorporation of carbon nanotubes.

State one physical property of HDPE that will be affected by the incorporation of carbon nanotubes.

State one physical property of HDPE that will be affected by the incorporation of carbon nanotubes.

Describe how carbon nanotubes are produced by chemical vapour deposition (CVD).

Describe how carbon nanotubes are produced by chemical vapour deposition (CVD).

Describe how carbon nanotubes are produced by chemical vapour deposition (CVD).

State the property of carbon nanotubes that enables them to form a nematic liquid crystal phase.

State the property of carbon nanotubes that enables them to form a nematic liquid crystal phase.

State the property of carbon nanotubes that enables them to form a nematic liquid crystal phase.

Both of these are thermoplastic polymers. Outline what this term means.

Both of these are thermoplastic polymers. Outline what this term means.

Both of these are thermoplastic polymers. Outline what this term means.

Compare and contrast the structures of HDPE and LDPE.

Compare and contrast the structures of HDPE and LDPE.

Compare and contrast the structures of HDPE and LDPE.

State one way in which a physical property of HDPE, other than density, differs from that of LDPE as a result of this structural difference.

State one way in which a physical property of HDPE, other than density, differs from that of LDPE as a result of this structural difference.

State one way in which a physical property of HDPE, other than density, differs from that of LDPE as a result of this structural difference.

The production of HDPE involves the use of homogeneous catalysts. Outline how homogeneous catalysts reduce the activation energy of reactions.

The production of HDPE involves the use of homogeneous catalysts. Outline how homogeneous catalysts reduce the activation energy of reactions.

The production of HDPE involves the use of homogeneous catalysts. Outline how homogeneous catalysts reduce the activation energy of reactions.

Trace amounts of metal from the catalysts used in the production of HDPE sometimes remain in the product. State a technique that could be used to measure the concentration of the metal.

Trace amounts of metal from the catalysts used in the production of HDPE sometimes remain in the product. State a technique that could be used to measure the concentration of the metal.

Trace amounts of metal from the catalysts used in the production of HDPE sometimes remain in the product. State a technique that could be used to measure the concentration of the metal.

Suggest two of the major obstacles, other than collection and economic factors, which have to be overcome in plastic recycling.

Suggest two of the major obstacles, other than collection and economic factors, which have to be overcome in plastic recycling.

Suggest two of the major obstacles, other than collection and economic factors, which have to be overcome in plastic recycling.

State one factor that increases the rate at which saturated lipids become rancid.

State one factor that increases the rate at which saturated lipids become rancid.

State one factor that increases the rate at which saturated lipids become rancid.

Plastics are another source of marine pollution. Outline one way in which plastics can be made more biodegradable.

Plastics are another source of marine pollution. Outline one way in which plastics can be made more biodegradable.

Plastics are another source of marine pollution. Outline one way in which plastics can be made more biodegradable.

A person with diabetes suffering very low blood sugar (hypoglycaemia) may be advised to consume glucose immediately and then eat a small amount of starchy food such as a sandwich. Explain this advice in terms of the properties of glucose and starch.

A person with diabetes suffering very low blood sugar (hypoglycaemia) may be advised to consume glucose immediately and then eat a small amount of starchy food such as a sandwich. Explain this advice in terms of the properties of glucose and starch.

A person with diabetes suffering very low blood sugar (hypoglycaemia) may be advised to consume glucose immediately and then eat a small amount of starchy food such as a sandwich. Explain this advice in terms of the properties of glucose and starch.

Morphine and codeine are strong analgesics. Outline how strong analgesics function.

Morphine and codeine are strong analgesics. Outline how strong analgesics function.

Morphine and codeine are strong analgesics. Outline how strong analgesics function.

Explain how omeprazole (Prilosec) reduces stomach acidity.

Explain how omeprazole (Prilosec) reduces stomach acidity.

Explain how omeprazole (Prilosec) reduces stomach acidity.

Shikimic acid, the precursor for oseltamivir (Tamiflu), was originally extracted from star anise, and is now produced using genetically modified E. coli bacteria.

Suggest one difficulty associated with synthesizing oseltamivir (Tamiflu) from star anise.

Shikimic acid, the precursor for oseltamivir (Tamiflu), was originally extracted from star anise, and is now produced using genetically modified E. coli bacteria.

Suggest one difficulty associated with synthesizing oseltamivir (Tamiflu) from star anise.

Shikimic acid, the precursor for oseltamivir (Tamiflu), was originally extracted from star anise, and is now produced using genetically modified E. coli bacteria.

Suggest one difficulty associated with synthesizing oseltamivir (Tamiflu) from star anise.

Identify one naturally occurring greenhouse gas, other than carbon dioxide or water vapour, and its natural source.

Identify one naturally occurring greenhouse gas, other than carbon dioxide or water vapour, and its natural source.

Identify one naturally occurring greenhouse gas, other than carbon dioxide or water vapour, and its natural source.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

State the formula of a fuel that might be produced from the vegetable oil whose formula is shown.

Outline why biofuels are considered more environmentally friendly, even though they produce more carbon dioxide per kJ of energy than petroleum based fuels.

Outline why biofuels are considered more environmentally friendly, even though they produce more carbon dioxide per kJ of energy than petroleum based fuels.

Outline why biofuels are considered more environmentally friendly, even though they produce more carbon dioxide per kJ of energy than petroleum based fuels.

Compare and contrast the IR spectrum of aspirin with that of salicylic acid, using section 26 of the data booklet.

Compare and contrast the IR spectrum of aspirin with that of salicylic acid, using section 26 of the data booklet.

Compare and contrast the IR spectrum of aspirin with that of salicylic acid, using section 26 of the data booklet.

An antacid tablet contains 680 mg of calcium carbonate, CaCO₃, and 80 mg of magnesium carbonate, MgCO₃.

State the equation for the reaction of magnesium carbonate with hydrochloric acid.

An antacid tablet contains 680 mg of calcium carbonate, CaCO₃, and 80 mg of magnesium carbonate, MgCO₃.

State the equation for the reaction of magnesium carbonate with hydrochloric acid.

An antacid tablet contains 680 mg of calcium carbonate, CaCO₃, and 80 mg of magnesium carbonate, MgCO₃.

State the equation for the reaction of magnesium carbonate with hydrochloric acid.

Butter contains varying proportions of oleic, myristic, palmitic and stearic acids. Explain in terms of their structures why stearic acid has a higher melting point than oleic acid, using section 34 of the data booklet.

Butter contains varying proportions of oleic, myristic, palmitic and stearic acids. Explain in terms of their structures why stearic acid has a higher melting point than oleic acid, using section 34 of the data booklet.

Butter contains varying proportions of oleic, myristic, palmitic and stearic acids. Explain in terms of their structures why stearic acid has a higher melting point than oleic acid, using section 34 of the data booklet.

Explain why sharks and swordfish sometimes contain high concentrations of mercury and polychlorinated biphenyls (PCBs).

Explain why sharks and swordfish sometimes contain high concentrations of mercury and polychlorinated biphenyls (PCBs).

Explain why sharks and swordfish sometimes contain high concentrations of mercury and polychlorinated biphenyls (PCBs).

State the specific type of linkage formed between α-glucose fragments in both maltose and amylose.

State the specific type of linkage formed between α-glucose fragments in both maltose and amylose.

State the specific type of linkage formed between α-glucose fragments in both maltose and amylose.

Determine the specific energy and energy density of petrol (gasoline), using data from sections 1 and 13 of the data booklet. Assume petrol is pure octane, C₈H₁₈. Octane: molar mass = 114.26 g mol⁻¹, density = 0.703 g cm⁻³.

Determine the specific energy and energy density of petrol (gasoline), using data from sections 1 and 13 of the data booklet. Assume petrol is pure octane, C₈H₁₈. Octane: molar mass = 114.26 g mol⁻¹, density = 0.703 g cm⁻³.

Determine the specific energy and energy density of petrol (gasoline), using data from sections 1 and 13 of the data booklet. Assume petrol is pure octane, C₈H₁₈. Octane: molar mass = 114.26 g mol⁻¹, density = 0.703 g cm⁻³.

Deduce the strongest intermolecular forces that would occur between the following amino acid residues in a protein chain.

Deduce the strongest intermolecular forces that would occur between the following amino acid residues in a protein chain.

Deduce the strongest intermolecular forces that would occur between the following amino acid residues in a protein chain.

Outline how the amino acids may be identified from a paper chromatogram.

Outline how the amino acids may be identified from a paper chromatogram.

Outline how the amino acids may be identified from a paper chromatogram.

Identify the type of rancidity occurring in saturated lipids and the structural feature that causes it.

Identify the type of rancidity occurring in saturated lipids and the structural feature that causes it.

Identify the type of rancidity occurring in saturated lipids and the structural feature that causes it.

The concentrations of oxygen and nitrogen in the atmosphere are much greater than those of greenhouse gases. Outline why these gases do not absorb infrared radiation.

The concentrations of oxygen and nitrogen in the atmosphere are much greater than those of greenhouse gases. Outline why these gases do not absorb infrared radiation.

The concentrations of oxygen and nitrogen in the atmosphere are much greater than those of greenhouse gases. Outline why these gases do not absorb infrared radiation.

Identify an element, other than carbon and hydrogen, found at significant concentrations in fossil fuels.

Identify an element, other than carbon and hydrogen, found at significant concentrations in fossil fuels.

Identify an element, other than carbon and hydrogen, found at significant concentrations in fossil fuels.

Petroleum contains many hydrocarbons. Explain how these are separated by fractional distillation.

Petroleum contains many hydrocarbons. Explain how these are separated by fractional distillation.

Petroleum contains many hydrocarbons. Explain how these are separated by fractional distillation.

Outline why the energy available from an engine will be less than these theoretical values.

Outline why the energy available from an engine will be less than these theoretical values.

Outline why the energy available from an engine will be less than these theoretical values.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

Outline the major technical problem affecting the direct use of vegetable oils as fuels in internal combustion engines and the chemical conversion that has overcome this.

Suggest one reason why there is opposition to the increased use of nuclear fission reactors.

Suggest one reason why there is opposition to the increased use of nuclear fission reactors.

Suggest one reason why there is opposition to the increased use of nuclear fission reactors.

Aspirin is often taken to reduce pain, swelling or fever. State one other use of aspirin.

Aspirin is often taken to reduce pain, swelling or fever. State one other use of aspirin.

Aspirin is often taken to reduce pain, swelling or fever. State one other use of aspirin.

State what is meant by the bioavailability of a drug.

State what is meant by the bioavailability of a drug.

State what is meant by the bioavailability of a drug.

Formulate an equation that shows how aqueous carbon dioxide produces hydrogen ions, H⁺(aq).

Formulate an equation that shows how aqueous carbon dioxide produces hydrogen ions, H⁺(aq).

Formulate an equation that shows how aqueous carbon dioxide produces hydrogen ions, H⁺(aq).

Outline how the bioavailability of aspirin may be increased.

Outline how the bioavailability of aspirin may be increased.

Outline how the bioavailability of aspirin may be increased.

Describe how penicillin combats bacterial infections.

Describe how penicillin combats bacterial infections.

Describe how penicillin combats bacterial infections.

Outline two consequences of prescribing antibiotics such as penicillin unnecessarily.

Outline two consequences of prescribing antibiotics such as penicillin unnecessarily.

Outline two consequences of prescribing antibiotics such as penicillin unnecessarily.

State how penicillins may be modified to increase their effectiveness.

State how penicillins may be modified to increase their effectiveness.

State how penicillins may be modified to increase their effectiveness.

Suggest one reason why codeine is more widely used than morphine as an analgesic.

Suggest one reason why codeine is more widely used than morphine as an analgesic.

Suggest one reason why codeine is more widely used than morphine as an analgesic.

Determine the amount, in mol, of hydrochloric acid neutralized by one antacid tablet.

Determine the amount, in mol, of hydrochloric acid neutralized by one antacid tablet.

Determine the amount, in mol, of hydrochloric acid neutralized by one antacid tablet.

Oseltamivir (Tamiflu) and zanamivir (Relenza) are used against flu viruses. Explain how these drugs function.

Oseltamivir (Tamiflu) and zanamivir (Relenza) are used against flu viruses. Explain how these drugs function.

Oseltamivir (Tamiflu) and zanamivir (Relenza) are used against flu viruses. Explain how these drugs function.

ICP-OES/MS can be used to analyse alloys and composites. Distinguish between alloys and composites.

ICP-OES/MS can be used to analyse alloys and composites. Distinguish between alloys and composites.

ICP-OES/MS can be used to analyse alloys and composites. Distinguish between alloys and composites.

ICP-MS is a reference mode for analysis. The following correlation graphs between ICP-OES and ICP-MS were produced for yttrium and nickel.

Each y-axis shows concentrations calculated by ICP-OES; each x-axis shows concentrations for the same sample as found by ICP-MS.

The line in each graph is y = x.

Discuss the effectiveness of ICP-OES for yttrium and nickel.

ICP-MS is a reference mode for analysis. The following correlation graphs between ICP-OES and ICP-MS were produced for yttrium and nickel.

Each y-axis shows concentrations calculated by ICP-OES; each x-axis shows concentrations for the same sample as found by ICP-MS.

The line in each graph is y = x.

Discuss the effectiveness of ICP-OES for yttrium and nickel.

ICP-MS is a reference mode for analysis. The following correlation graphs between ICP-OES and ICP-MS were produced for yttrium and nickel.

Each y-axis shows concentrations calculated by ICP-OES; each x-axis shows concentrations for the same sample as found by ICP-MS.

The line in each graph is y = x.

Discuss the effectiveness of ICP-OES for yttrium and nickel.

Identify the purpose of each graph.

Identify the purpose of each graph.

Identify the purpose of each graph.

Calculate, to four significant figures, the concentration, in μg kg⁻¹, of vanadium in oil giving a signal intensity of 14 950.

Calculate, to four significant figures, the concentration, in μg kg⁻¹, of vanadium in oil giving a signal intensity of 14 950.

Calculate, to four significant figures, the concentration, in μg kg⁻¹, of vanadium in oil giving a signal intensity of 14 950.

Vanadium(V) oxide is used as the catalyst in the conversion of sulfur dioxide to sulfur trioxide.

SO₂(g) + V₂O₅(s) → SO₃(g) + 2VO₂(s)

$\frac{1}{2}$O₂(g) + 2VO₂(s) → V₂O₅(s)

Outline how vanadium(V) oxide acts as a catalyst.

Vanadium(V) oxide is used as the catalyst in the conversion of sulfur dioxide to sulfur trioxide.

SO₂(g) + V₂O₅(s) → SO₃(g) + 2VO₂(s)

$\frac{1}{2}$O₂(g) + 2VO₂(s) → V₂O₅(s)

Outline how vanadium(V) oxide acts as a catalyst.

Vanadium(V) oxide is used as the catalyst in the conversion of sulfur dioxide to sulfur trioxide.

SO₂(g) + V₂O₅(s) → SO₃(g) + 2VO₂(s)

$\frac{1}{2}$O₂(g) + 2VO₂(s) → V₂O₅(s)

Outline how vanadium(V) oxide acts as a catalyst.

Sketch four repeating units of the polymer to show atactic and isotactic polypropene.

Sketch four repeating units of the polymer to show atactic and isotactic polypropene.

Sketch four repeating units of the polymer to show atactic and isotactic polypropene.

State the chemical reason why plastics do not degrade easily.

State the chemical reason why plastics do not degrade easily.

State the chemical reason why plastics do not degrade easily.

State the source of carbon for MWCNT produced by arc discharge and by CVD.

State the source of carbon for MWCNT produced by arc discharge and by CVD.

State the source of carbon for MWCNT produced by arc discharge and by CVD.

Discuss three properties a substance should have to be suitable for use in liquid crystal displays.

Discuss three properties a substance should have to be suitable for use in liquid crystal displays.

Discuss three properties a substance should have to be suitable for use in liquid crystal displays.

Identify the type of chemical reaction that occurs between fatty acids and glycerol to form lipids and the by-product of the reaction.

Identify the type of chemical reaction that occurs between fatty acids and glycerol to form lipids and the by-product of the reaction.

Identify the type of chemical reaction that occurs between fatty acids and glycerol to form lipids and the by-product of the reaction.

Deduce the structure of the lipid formed by the reaction between lauric acid and glycerol (propane-1,2,3-triol) using section 34 of the data booklet.

Deduce the structure of the lipid formed by the reaction between lauric acid and glycerol (propane-1,2,3-triol) using section 34 of the data booklet.

Deduce the structure of the lipid formed by the reaction between lauric acid and glycerol (propane-1,2,3-triol) using section 34 of the data booklet.

Outline one impact food labelling has had on the consumption of foods containing different types of lipids.

Outline one impact food labelling has had on the consumption of foods containing different types of lipids.

Outline one impact food labelling has had on the consumption of foods containing different types of lipids.

Green Chemistry reduces the production of hazardous materials and chemical waste.

Outline two specific examples or technological processes of how Green Chemistry has accomplished this environmental impact.

Green Chemistry reduces the production of hazardous materials and chemical waste.

Outline two specific examples or technological processes of how Green Chemistry has accomplished this environmental impact.

Explain the solubility of vitamins A and C using section 35 of the data booklet.

Explain the solubility of vitamins A and C using section 35 of the data booklet.

Explain the molecular mechanism by which carbon dioxide acts as a greenhouse gas.

Explain the molecular mechanism by which carbon dioxide acts as a greenhouse gas.

Explain the molecular mechanism by which carbon dioxide acts as a greenhouse gas.

Power plants generating electricity by burning coal to boil water operate at approximately 35% efficiency.

State what this means and suggest why it is lower than the thermal efficiency.

Power plants generating electricity by burning coal to boil water operate at approximately 35% efficiency.

State what this means and suggest why it is lower than the thermal efficiency.

Power plants generating electricity by burning coal to boil water operate at approximately 35% efficiency.

State what this means and suggest why it is lower than the thermal efficiency.

Deduce the equation for the transesterification reaction of pentyl octanoate, C₇H₁₅COOC₅H₁₁, with methanol.

Deduce the equation for the transesterification reaction of pentyl octanoate, C₇H₁₅COOC₅H₁₁, with methanol.

Deduce the equation for the transesterification reaction of pentyl octanoate, C₇H₁₅COOC₅H₁₁, with methanol.

Drug testing is necessary to determine safe and effective doses.

Distinguish between the lethal dose (LD₅₀) and the toxic dose (TD₅₀).

Drug testing is necessary to determine safe and effective doses.

Distinguish between the lethal dose (LD₅₀) and the toxic dose (TD₅₀).

State the type of reaction used to synthesize aspirin from salicylic acid.

State the type of reaction used to synthesize aspirin from salicylic acid.

State the type of reaction used to synthesize aspirin from salicylic acid.

Explain why aspirin is not stored in a hot, humid location.

Explain why aspirin is not stored in a hot, humid location.

Explain why aspirin is not stored in a hot, humid location.

Morphine and diamorphine (heroin) are both opioids.

Explain why diamorphine is more potent than morphine using section 37 of the data booklet.

Morphine and diamorphine (heroin) are both opioids.

Explain why diamorphine is more potent than morphine using section 37 of the data booklet.

Drug synthesis often involves solvents.

Identify a common hazardous solvent and a Green solvent that could replace it.

Drug synthesis often involves solvents.

Identify a common hazardous solvent and a Green solvent that could replace it.

Arachidonic acid is a polyunsaturated omega-6 fatty acid found in peanut oil.

Determine the number of carbon–carbon double bonds present if the iodine number for the compound is 334. (Arachidonic acid M_r = 304.5)

Arachidonic acid is a polyunsaturated omega-6 fatty acid found in peanut oil.

Determine the number of carbon–carbon double bonds present if the iodine number for the compound is 334. (Arachidonic acid M_r = 304.5)

Arachidonic acid is a polyunsaturated omega-6 fatty acid found in peanut oil.

Determine the number of carbon–carbon double bonds present if the iodine number for the compound is 334. (Arachidonic acid M_r = 304.5)

Explain why lipids provide more energy than carbohydrates and proteins.

Explain why lipids provide more energy than carbohydrates and proteins.

Explain why lipids provide more energy than carbohydrates and proteins.

Outline how higher octane fuels help eliminate “knocking” in engines.

Outline how higher octane fuels help eliminate “knocking” in engines.

Outline how higher octane fuels help eliminate “knocking” in engines.

Draw the dipeptide represented by the formula Ala-Gly using section 33 of the data booklet.

Draw the dipeptide represented by the formula Ala-Gly using section 33 of the data booklet.

Draw the dipeptide represented by the formula Ala-Gly using section 33 of the data booklet.

Outline why amino acids have high melting points.

Outline why amino acids have high melting points.

Outline why amino acids have high melting points.

Outline two reasons why oil is one of the world’s significant energy sources.

Outline two reasons why oil is one of the world’s significant energy sources.

Outline two reasons why oil is one of the world’s significant energy sources.

Formulate an equation for the cracking of C₁₆H₃₄ into two products with eight carbon atoms each.

Formulate an equation for the cracking of C₁₆H₃₄ into two products with eight carbon atoms each.

Formulate an equation for the cracking of C₁₆H₃₄ into two products with eight carbon atoms each.

Identify, giving a reason, which product in (b)(i) could be used in petrol (gasoline).

Identify, giving a reason, which product in (b)(i) could be used in petrol (gasoline).

Identify, giving a reason, which product in (b)(i) could be used in petrol (gasoline).

The performance of hydrocarbons as fuels can be improved by catalytic reforming.

Outline how catalytic reforming increases a fuel’s octane rating.

The performance of hydrocarbons as fuels can be improved by catalytic reforming.

Outline how catalytic reforming increases a fuel’s octane rating.

The performance of hydrocarbons as fuels can be improved by catalytic reforming.

Outline how catalytic reforming increases a fuel’s octane rating.

Discuss the significance of two greenhouse gases, other than carbon dioxide, in causing global warming or climate change.

Discuss the significance of two greenhouse gases, other than carbon dioxide, in causing global warming or climate change.

Discuss the significance of two greenhouse gases, other than carbon dioxide, in causing global warming or climate change.

Calculate the thermal efficiency of a steam turbine supplied with steam at 540°C and using a river as the choice of sink at 23 °C.

Calculate the thermal efficiency of a steam turbine supplied with steam at 540°C and using a river as the choice of sink at 23 °C.

Calculate the thermal efficiency of a steam turbine supplied with steam at 540°C and using a river as the choice of sink at 23 °C.

Compare and contrast the process of nuclear fusion with nuclear fission.

Compare and contrast the process of nuclear fusion with nuclear fission.

Compare and contrast the process of nuclear fusion with nuclear fission.

Dubnium-261 has a half-life of 27 seconds and rutherfordium-261 has a half-life of 81 seconds.

Estimate what fraction of the dubnium-261 isotope remains in the same amount of time that $\frac{3}{4}$ of rutherfordium-261 decays.

Dubnium-261 has a half-life of 27 seconds and rutherfordium-261 has a half-life of 81 seconds.

Estimate what fraction of the dubnium-261 isotope remains in the same amount of time that $\frac{3}{4}$ of rutherfordium-261 decays.

Dubnium-261 has a half-life of 27 seconds and rutherfordium-261 has a half-life of 81 seconds.

Estimate what fraction of the dubnium-261 isotope remains in the same amount of time that $\frac{3}{4}$ of rutherfordium-261 decays.

Outline why the ester product of this reaction is a better diesel fuel than pentyl octanoate.

Outline why the ester product of this reaction is a better diesel fuel than pentyl octanoate.

Outline why the ester product of this reaction is a better diesel fuel than pentyl octanoate.

Describe how penicillin combats bacterial infections.

Describe how penicillin combats bacterial infections.

Describe how penicillin combats bacterial infections.

State how penicillins may be modified to increase their effectiveness.

State how penicillins may be modified to increase their effectiveness.

State how penicillins may be modified to increase their effectiveness.

Formulate a chemical equation for the neutralization of stomach acid with calcium carbonate.

Formulate a chemical equation for the neutralization of stomach acid with calcium carbonate.

Formulate a chemical equation for the neutralization of stomach acid with calcium carbonate.

Calculate the amount, in mol, of stomach acid neutralized by an antacid tablet containing 0.750 g calcium carbonate.

Calculate the amount, in mol, of stomach acid neutralized by an antacid tablet containing 0.750 g calcium carbonate.

Calculate the amount, in mol, of stomach acid neutralized by an antacid tablet containing 0.750 g calcium carbonate.

Identify the names of two functional groups present in zanamivir using section 37 of the data booklet.

Identify the names of two functional groups present in zanamivir using section 37 of the data booklet.

Identify the names of two functional groups present in zanamivir using section 37 of the data booklet.

Distinguish between bacteria and viruses.

Distinguish between bacteria and viruses.

Distinguish between bacteria and viruses.

State one way in which viruses differ from bacteria.

State one way in which viruses differ from bacteria.

State one way in which viruses differ from bacteria.

Formulate equation(s) for the conversion of coal and steam to methane.

Formulate equation(s) for the conversion of coal and steam to methane.

Formulate equation(s) for the conversion of coal and steam to methane.

Structures of poly(methyl acrylate), PMA, and Bakelite^® are shown.

Suggest, giving reasons, which is the thermoplastic polymer and which is the thermosetting polymer.

Structures of poly(methyl acrylate), PMA, and Bakelite^® are shown.

Suggest, giving reasons, which is the thermoplastic polymer and which is the thermosetting polymer.

Structures of poly(methyl acrylate), PMA, and Bakelite^® are shown.

Suggest, giving reasons, which is the thermoplastic polymer and which is the thermosetting polymer.

Determine the pH of a buffer solution that is 0.0100 mol dm⁻³ sodium hydrogen carbonate and 0.0200 mol dm⁻³ sodium carbonate, using section 1 of the data booklet.

K_a (hydrogen carbonate ion) = 4.8 × 10⁻¹¹

Determine the pH of a buffer solution that is 0.0100 mol dm⁻³ sodium hydrogen carbonate and 0.0200 mol dm⁻³ sodium carbonate, using section 1 of the data booklet.

K_a (hydrogen carbonate ion) = 4.8 × 10⁻¹¹

Determine the pH of a buffer solution that is 0.0100 mol dm⁻³ sodium hydrogen carbonate and 0.0200 mol dm⁻³ sodium carbonate, using section 1 of the data booklet.

K_a (hydrogen carbonate ion) = 4.8 × 10⁻¹¹

Suggest two reasons why chlorinated solvents should neither be released into the atmosphere nor incinerated (burnt).

Suggest two reasons why chlorinated solvents should neither be released into the atmosphere nor incinerated (burnt).

In an incomplete combustion of the polyvinyl chloride, PVC, it was found that hydrogen chloride, carbon monoxide, carbon dioxide, and water vapour were released.

Formulate an equation for this reaction using the formula of the PVC repeating unit.

In an incomplete combustion of the polyvinyl chloride, PVC, it was found that hydrogen chloride, carbon monoxide, carbon dioxide, and water vapour were released.

Formulate an equation for this reaction using the formula of the PVC repeating unit.

In an incomplete combustion of the polyvinyl chloride, PVC, it was found that hydrogen chloride, carbon monoxide, carbon dioxide, and water vapour were released.

Formulate an equation for this reaction using the formula of the PVC repeating unit.

Formulate equation(s) for the conversion of coal and steam to methane.

Formulate equation(s) for the conversion of coal and steam to methane.

Formulate equation(s) for the conversion of coal and steam to methane.

Deduce the reduction half-equation at the cathode.

Deduce the reduction half-equation at the cathode.

Deduce the reduction half-equation at the cathode.

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

An unknown antacid sample has a lead ion concentration of 0.50 μg dm^‒3.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

An unknown antacid sample has a lead ion concentration of 0.50 μg dm^‒3.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

An unknown antacid sample has a lead ion concentration of 0.50 μg dm^‒3.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

Explain why carbon monoxide is very toxic and how it may be possible to treat carbon monoxide poisoning.

Explain why carbon monoxide is very toxic and how it may be possible to treat carbon monoxide poisoning.

Explain why carbon monoxide is very toxic and how it may be possible to treat carbon monoxide poisoning.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

State the equation for the reaction of calcium carbonate, the active ingredient in some antacids, with stomach acid.

State the equation for the reaction of calcium carbonate, the active ingredient in some antacids, with stomach acid.

State the equation for the reaction of calcium carbonate, the active ingredient in some antacids, with stomach acid.

An aqueous lead(II) ion reacts with three ethane-1,2-diamine molecules to form an octahedral chelate ion.

Outline why the chelate ion is more stable than the reactants.

An aqueous lead(II) ion reacts with three ethane-1,2-diamine molecules to form an octahedral chelate ion.

Outline why the chelate ion is more stable than the reactants.

An aqueous lead(II) ion reacts with three ethane-1,2-diamine molecules to form an octahedral chelate ion.

Outline why the chelate ion is more stable than the reactants.

Suggest why the percentage of technetium-99m remaining in the human body two days after injection will be lower than that calculated in (b)(i).

Suggest why the percentage of technetium-99m remaining in the human body two days after injection will be lower than that calculated in (b)(i).

Suggest why the percentage of technetium-99m remaining in the human body two days after injection will be lower than that calculated in (b)(i).

Comment on the specific energies of hydrogen and methane.

Comment on the specific energies of hydrogen and methane.

Comment on the specific energies of hydrogen and methane.

Calculate the specific energy, in kJ g⁻¹, of methane.

Calculate the specific energy, in kJ g⁻¹, of methane.

Calculate the specific energy, in kJ g⁻¹, of methane.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.

The diagram shows part of a Taxol molecule in skeletal form.

Draw a circle around each chiral carbon.

The diagram shows part of a Taxol molecule in skeletal form.

Draw a circle around each chiral carbon.

The diagram shows part of a Taxol molecule in skeletal form.

Draw a circle around each chiral carbon.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Arc discharge, consisting of two inert metal electrodes in a liquid solvent, is one method of producing carbon nanotubes (CNTs).

Predict, giving a reason, the electrode at which the solvent cyclohexane, C₆H₁₂, will decompose to form CNTs.

Arc discharge, consisting of two inert metal electrodes in a liquid solvent, is one method of producing carbon nanotubes (CNTs).

Predict, giving a reason, the electrode at which the solvent cyclohexane, C₆H₁₂, will decompose to form CNTs.

Arc discharge, consisting of two inert metal electrodes in a liquid solvent, is one method of producing carbon nanotubes (CNTs).

Predict, giving a reason, the electrode at which the solvent cyclohexane, C₆H₁₂, will decompose to form CNTs.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Outline why this type of classification is not entirely satisfactory by using magnesium diboride, MgB₂, as an example. Refer to sections 8 and 29 of the data booklet.

Comment on the specific energies of hydrogen and methane.

Comment on the specific energies of hydrogen and methane.

Comment on the specific energies of hydrogen and methane.

A voltaic cell consists of a nickel electrode in 1.0 mol dm⁻³ Ni²⁺ (aq) solution and a cadmium electrode in a Cd²⁺ (aq) solution of unknown concentration.

Cd (s) + Ni²⁺ (aq) → Cd²⁺ (aq) + Ni (s)               E^Θ_cell = 0.14 V

Determine the concentration of the Cd²⁺ (aq) solution if the cell voltage, E, is 0.19 V at 298 K. Use section 1 of the data booklet.

A voltaic cell consists of a nickel electrode in 1.0 mol dm⁻³ Ni²⁺ (aq) solution and a cadmium electrode in a Cd²⁺ (aq) solution of unknown concentration.

Cd (s) + Ni²⁺ (aq) → Cd²⁺ (aq) + Ni (s)               E^Θ_cell = 0.14 V

Determine the concentration of the Cd²⁺ (aq) solution if the cell voltage, E, is 0.19 V at 298 K. Use section 1 of the data booklet.

A voltaic cell consists of a nickel electrode in 1.0 mol dm⁻³ Ni²⁺ (aq) solution and a cadmium electrode in a Cd²⁺ (aq) solution of unknown concentration.

Cd (s) + Ni²⁺ (aq) → Cd²⁺ (aq) + Ni (s)               E^Θ_cell = 0.14 V

Determine the concentration of the Cd²⁺ (aq) solution if the cell voltage, E, is 0.19 V at 298 K. Use section 1 of the data booklet.

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Electrolysis is used to obtain lead from Pb²⁺ (aq) solution.

Determine the time, in hours, required to produce 0.0500 mol lead using a current (I) of 1.34 A. Use section 2 of the data booklet and the equation, charge (Q) = current (I) × time (t, in seconds).

Deduce a Lewis (electron dot) structure of the superoxide, O₂^–, free radical.

Deduce a Lewis (electron dot) structure of the superoxide, O₂^–, free radical.

Deduce a Lewis (electron dot) structure of the superoxide, O₂^–, free radical.

Repeating units of several polymers are listed.

The infrared (IR) spectrum of one of these polymers is shown.

Deduce, giving a reason, the name of this polymer and its Resin Identification Code (RIC), using sections 26 and 30 in the data booklet.

Repeating units of several polymers are listed.

The infrared (IR) spectrum of one of these polymers is shown.

Deduce, giving a reason, the name of this polymer and its Resin Identification Code (RIC), using sections 26 and 30 in the data booklet.

Repeating units of several polymers are listed.

The infrared (IR) spectrum of one of these polymers is shown.

Deduce, giving a reason, the name of this polymer and its Resin Identification Code (RIC), using sections 26 and 30 in the data booklet.

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

Calculate the mass, in kg, of carbon dioxide produced by the complete combustion of 72.0 dm³ octane, C₈H₁₈.

Density of C₈H₁₈ = 703 g dm⁻³

C₈H₁₈ (l) + 12.5O₂ (g) → 8CO₂ (g) + 9H₂O (g)

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

State an analytical technique used to separate anabolic steroids from other compounds in an athlete’s urine or blood.

State an analytical technique used to separate anabolic steroids from other compounds in an athlete’s urine or blood.

State an analytical technique used to separate anabolic steroids from other compounds in an athlete’s urine or blood.

Ethanol in breath can be detected by a redox reaction. Outline this method of detection. An equation is not required.

Ethanol in breath can be detected by a redox reaction. Outline this method of detection. An equation is not required.

Ethanol in breath can be detected by a redox reaction. Outline this method of detection. An equation is not required.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

Calculate the concentration of lead ions in the sample in mol dm^‒3.

Lead ions are toxic and can be precipitated using hydroxide ions.

Pb²⁺ (aq) + 2OH^‒ (aq) $\rightleftharpoons$ Pb(OH)₂ (s)

Sufficient sodium hydroxide solid is added to the antacid sample to produce a 1.0 × 10^‒2 mol dm^‒3 hydroxide ion solution at 298 K.

Deduce if a precipitate will be formed, using section 32 of the data booklet.

If you did not calculate the concentration of lead ions in (b)(i), use the value of 2.4 × 10⁻⁴ mol dm^‒3, but this is not the correct value.

Lead ions are toxic and can be precipitated using hydroxide ions.

Pb²⁺ (aq) + 2OH^‒ (aq) $\rightleftharpoons$ Pb(OH)₂ (s)

Sufficient sodium hydroxide solid is added to the antacid sample to produce a 1.0 × 10^‒2 mol dm^‒3 hydroxide ion solution at 298 K.

Deduce if a precipitate will be formed, using section 32 of the data booklet.

If you did not calculate the concentration of lead ions in (b)(i), use the value of 2.4 × 10⁻⁴ mol dm^‒3, but this is not the correct value.

Lead ions are toxic and can be precipitated using hydroxide ions.

Pb²⁺ (aq) + 2OH^‒ (aq) $\rightleftharpoons$ Pb(OH)₂ (s)

Sufficient sodium hydroxide solid is added to the antacid sample to produce a 1.0 × 10^‒2 mol dm^‒3 hydroxide ion solution at 298 K.

Deduce if a precipitate will be formed, using section 32 of the data booklet.

If you did not calculate the concentration of lead ions in (b)(i), use the value of 2.4 × 10⁻⁴ mol dm^‒3, but this is not the correct value.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Explain why diamorphine (heroin) crosses the blood–brain barrier more easily than morphine.

Alpha particles are more damaging to human cells than any other nuclear radiation and yet they are used in targeted alpha therapy (TAT).

Explain how TAT is relatively safe to use in the treatment of dispersed cancers.

Alpha particles are more damaging to human cells than any other nuclear radiation and yet they are used in targeted alpha therapy (TAT).

Explain how TAT is relatively safe to use in the treatment of dispersed cancers.

Alpha particles are more damaging to human cells than any other nuclear radiation and yet they are used in targeted alpha therapy (TAT).

Explain how TAT is relatively safe to use in the treatment of dispersed cancers.

Calculate the number of atoms per unit cell of gold, showing your working.

Calculate the number of atoms per unit cell of gold, showing your working.

Calculate the number of atoms per unit cell of gold, showing your working.

Formulate half-equations for the reactions at the anode (negative electrode) and cathode (positive electrode) during discharge of a lithium-ion battery.

Formulate half-equations for the reactions at the anode (negative electrode) and cathode (positive electrode) during discharge of a lithium-ion battery.

Formulate half-equations for the reactions at the anode (negative electrode) and cathode (positive electrode) during discharge of a lithium-ion battery.

The edge length of the gold unit cell is 4.08 × 10^‒8 cm.

Determine the density of gold in g cm^‒3, using sections 2 and 6 of the data booklet.

The edge length of the gold unit cell is 4.08 × 10^‒8 cm.

Determine the density of gold in g cm^‒3, using sections 2 and 6 of the data booklet.

The edge length of the gold unit cell is 4.08 × 10^‒8 cm.

Determine the density of gold in g cm^‒3, using sections 2 and 6 of the data booklet.

Contrast the actions of non-competitive and competitive inhibitors of an enzyme and state their effects on the maximum rate of reaction, V_max, and the Michaelis–Menten constant, K_m.

Contrast the actions of non-competitive and competitive inhibitors of an enzyme and state their effects on the maximum rate of reaction, V_max, and the Michaelis–Menten constant, K_m.

Contrast the actions of non-competitive and competitive inhibitors of an enzyme and state their effects on the maximum rate of reaction, V_max, and the Michaelis–Menten constant, K_m.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

The iodine number is the maximum mass of iodine that reacts with 100 g of an unsaturated compound.

Determine the iodine number of stearidonic acid, C₁₇H₂₇COOH.

Technetium-99m (${}_{43}^{99\text{m}}\text{Tc}$) has a half-life of 6.0 hours. Calculate the percentage of ${}_{43}^{99\text{m}}\text{Tc}$ remaining in a sample of the radioisotope after two days.

Technetium-99m (${}_{43}^{99\text{m}}\text{Tc}$) has a half-life of 6.0 hours. Calculate the percentage of ${}_{43}^{99\text{m}}\text{Tc}$ remaining in a sample of the radioisotope after two days.

Technetium-99m (${}_{43}^{99\text{m}}\text{Tc}$) has a half-life of 6.0 hours. Calculate the percentage of ${}_{43}^{99\text{m}}\text{Tc}$ remaining in a sample of the radioisotope after two days.

State one factor considered when making green chemistry polymers.

State one factor considered when making green chemistry polymers.

State one factor considered when making green chemistry polymers.

Lithium forms a crystalline lattice with the unit cell structure shown below.

X-ray diffraction shows that the length of the edge of the unit cell is 3.51 × 10⁻⁸ cm.

Determine the density of lithium, in g cm⁻³, using sections 2 and 6 of the data booklet.

Lithium forms a crystalline lattice with the unit cell structure shown below.

X-ray diffraction shows that the length of the edge of the unit cell is 3.51 × 10⁻⁸ cm.

Determine the density of lithium, in g cm⁻³, using sections 2 and 6 of the data booklet.

Lithium forms a crystalline lattice with the unit cell structure shown below.

X-ray diffraction shows that the length of the edge of the unit cell is 3.51 × 10⁻⁸ cm.

Determine the density of lithium, in g cm⁻³, using sections 2 and 6 of the data booklet.

Explain the effects of very low and high temperatures on the liquid-crystal behaviour of this molecule.

Low temperature:

High temperature:

Explain the effects of very low and high temperatures on the liquid-crystal behaviour of this molecule.

Low temperature:

High temperature:

Explain the effects of very low and high temperatures on the liquid-crystal behaviour of this molecule.

Low temperature:

High temperature:

Tyre fires emit trace quantities of polychlorinated dibenzofurans and polychlorinated dibenzo-p-dioxin.

Outline, using section 31 of the data booklet, why polychlorinated dibenzofuran is not classed chemically as a dioxin but considered “dioxin-like”.

Tyre fires emit trace quantities of polychlorinated dibenzofurans and polychlorinated dibenzo-p-dioxin.

Outline, using section 31 of the data booklet, why polychlorinated dibenzofuran is not classed chemically as a dioxin but considered “dioxin-like”.

Tyre fires emit trace quantities of polychlorinated dibenzofurans and polychlorinated dibenzo-p-dioxin.

Outline, using section 31 of the data booklet, why polychlorinated dibenzofuran is not classed chemically as a dioxin but considered “dioxin-like”.

Identify the colour of the emission spectrum of lithium using section 17 of the data booklet.

Identify the colour of the emission spectrum of lithium using section 17 of the data booklet.

Identify the colour of the emission spectrum of lithium using section 17 of the data booklet.

Suggest one application for carbon nanotubes.

Suggest one application for carbon nanotubes.

Suggest one application for carbon nanotubes.

Classify polybutadiene as either an addition or condensation polymer, giving a reason.

Classify polybutadiene as either an addition or condensation polymer, giving a reason.

Classify polybutadiene as either an addition or condensation polymer, giving a reason.

Suggest a better method.

Suggest a better method.

Suggest a better method.

Draw a circle around the functional group formed between the amino acids and state its name.

Name:

Draw a circle around the functional group formed between the amino acids and state its name.

Name:

Draw a circle around the functional group formed between the amino acids and state its name.

Name:

A mixture of phenylalanine and aspartic acid is separated by gel electrophoresis with a buffer of pH = 5.5.

Deduce their relative positions after electrophoresis, annotating them on the diagram. Use section 33 of the data booklet.

A mixture of phenylalanine and aspartic acid is separated by gel electrophoresis with a buffer of pH = 5.5.

Deduce their relative positions after electrophoresis, annotating them on the diagram. Use section 33 of the data booklet.

A mixture of phenylalanine and aspartic acid is separated by gel electrophoresis with a buffer of pH = 5.5.

Deduce their relative positions after electrophoresis, annotating them on the diagram. Use section 33 of the data booklet.

A Michaelis–Menten plot for an enzyme-catalysed reaction is shown.

Sketch a curve to show the effect of a competitive inhibitor.

A Michaelis–Menten plot for an enzyme-catalysed reaction is shown.

Sketch a curve to show the effect of a competitive inhibitor.

A Michaelis–Menten plot for an enzyme-catalysed reaction is shown.

Sketch a curve to show the effect of a competitive inhibitor.

Outline why the reaction releases energy.

Outline why the reaction releases energy.

Outline why the reaction releases energy.

Lithium is obtained by electrolysis of molten lithium chloride. Calculate the time, in seconds, taken to deposit 0.694 g Li using a current of 2.00 A.

Q (charge) = I (current) × t (time)

Lithium is obtained by electrolysis of molten lithium chloride. Calculate the time, in seconds, taken to deposit 0.694 g Li using a current of 2.00 A.

Q (charge) = I (current) × t (time)

Lithium is obtained by electrolysis of molten lithium chloride. Calculate the time, in seconds, taken to deposit 0.694 g Li using a current of 2.00 A.

Q (charge) = I (current) × t (time)

Explain how the inclusion of starch in plastics makes them biodegradable.

Explain how the inclusion of starch in plastics makes them biodegradable.

Explain how the inclusion of starch in plastics makes them biodegradable.

Aspartic acid is obtained synthetically as a racemic mixture. Draw the three‑dimensional shape of each isomer showing their spatial relationship to each other. Use section 33 of the data booklet.

Aspartic acid is obtained synthetically as a racemic mixture. Draw the three‑dimensional shape of each isomer showing their spatial relationship to each other. Use section 33 of the data booklet.

Aspartic acid is obtained synthetically as a racemic mixture. Draw the three‑dimensional shape of each isomer showing their spatial relationship to each other. Use section 33 of the data booklet.

Identify the type of bonding in lithium hydride, using sections 8 and 29 of the data booklet.

Identify the type of bonding in lithium hydride, using sections 8 and 29 of the data booklet.

Identify the type of bonding in lithium hydride, using sections 8 and 29 of the data booklet.

Suggest, giving a reason, how elastomers used for the tyre tread can increase the traction between the tyre and the road.

Suggest, giving a reason, how elastomers used for the tyre tread can increase the traction between the tyre and the road.

Suggest, giving a reason, how elastomers used for the tyre tread can increase the traction between the tyre and the road.

Methane can also be obtained by fractional distillation of crude oil.

[Source: Image used with kind permission of science-resources.co.uk]

Draw a circle on the diagram to show where the methane fraction is withdrawn.

Methane can also be obtained by fractional distillation of crude oil.

[Source: Image used with kind permission of science-resources.co.uk]

Draw a circle on the diagram to show where the methane fraction is withdrawn.

Methane can also be obtained by fractional distillation of crude oil.

[Source: Image used with kind permission of science-resources.co.uk]

Draw a circle on the diagram to show where the methane fraction is withdrawn.

The masses of the particles involved in this fission reaction are shown below.

Mass of neutron = 1.00867 amu
Mass of U-235 nucleus = 234.99346 amu
Mass of Ba-144 nucleus = 143.89223 amu
Mass of Kr-89 nucleus = 88.89788 amu

Determine the energy released, in J, when one uranium-235 nucleus undergoes fission. Use this data and information from sections 1 and 2 of the data booklet.

The masses of the particles involved in this fission reaction are shown below.

Mass of neutron = 1.00867 amu
Mass of U-235 nucleus = 234.99346 amu
Mass of Ba-144 nucleus = 143.89223 amu
Mass of Kr-89 nucleus = 88.89788 amu

Determine the energy released, in J, when one uranium-235 nucleus undergoes fission. Use this data and information from sections 1 and 2 of the data booklet.

The masses of the particles involved in this fission reaction are shown below.

Mass of neutron = 1.00867 amu
Mass of U-235 nucleus = 234.99346 amu
Mass of Ba-144 nucleus = 143.89223 amu
Mass of Kr-89 nucleus = 88.89788 amu

Determine the energy released, in J, when one uranium-235 nucleus undergoes fission. Use this data and information from sections 1 and 2 of the data booklet.

Formulate an equation for the neutralization of stomach acid with calcium carbonate, CaCO₃ (s).

Formulate an equation for the neutralization of stomach acid with calcium carbonate, CaCO₃ (s).

Formulate an equation for the neutralization of stomach acid with calcium carbonate, CaCO₃ (s).

Discuss how the difference in structure of two opiates, codeine and morphine, affect their ability to cross the blood–brain barrier. Use section 37 of the data booklet.

Discuss how the difference in structure of two opiates, codeine and morphine, affect their ability to cross the blood–brain barrier. Use section 37 of the data booklet.

Discuss how the difference in structure of two opiates, codeine and morphine, affect their ability to cross the blood–brain barrier. Use section 37 of the data booklet.

Technetium-99 decays further, emitting beta radiation. Formulate the equation for the decay of technetium-99.

Technetium-99 decays further, emitting beta radiation. Formulate the equation for the decay of technetium-99.

Technetium-99 decays further, emitting beta radiation. Formulate the equation for the decay of technetium-99.

Outline what is meant by low-level waste.

Outline what is meant by low-level waste.

Outline what is meant by low-level waste.

Lithium has shown some superconductive properties when doped into graphene or when under high pressure. Under high pressure, however, the Meissner effect is absent.

Describe the Meissner effect.

Lithium has shown some superconductive properties when doped into graphene or when under high pressure. Under high pressure, however, the Meissner effect is absent.

Describe the Meissner effect.

Lithium has shown some superconductive properties when doped into graphene or when under high pressure. Under high pressure, however, the Meissner effect is absent.

Describe the Meissner effect.

Outline two differences between heterogeneous and homogeneous catalysts.

Outline two differences between heterogeneous and homogeneous catalysts.

Outline two differences between heterogeneous and homogeneous catalysts.

Fats contain triglycerides that are esters of glycerol and fatty acids. Deduce an equation for the acid hydrolysis of the following triglyceride.

Fats contain triglycerides that are esters of glycerol and fatty acids. Deduce an equation for the acid hydrolysis of the following triglyceride.

Fats contain triglycerides that are esters of glycerol and fatty acids. Deduce an equation for the acid hydrolysis of the following triglyceride.

Describe the structure and bonding of a carbon nanotube.

Structure:

Bonding:

Describe the structure and bonding of a carbon nanotube.

Structure:

Bonding:

Describe the structure and bonding of a carbon nanotube.

Structure:

Bonding:

State the number of coordinate covalent bonds EDTA forms with Ni²⁺.

State the number of coordinate covalent bonds EDTA forms with Ni²⁺.

State the number of coordinate covalent bonds EDTA forms with Ni²⁺.

Outline one benefit of the use of these products.

Outline one benefit of the use of these products.

Outline one benefit of the use of these products.

Compare methane’s atmospheric abundance and greenhouse effect to that of carbon dioxide.

Compare methane’s atmospheric abundance and greenhouse effect to that of carbon dioxide.

Compare methane’s atmospheric abundance and greenhouse effect to that of carbon dioxide.

Suggest why ICP-OES does not give good quantitative results for distinguishing ⁶Li from naturally occurring lithium.

Suggest why ICP-OES does not give good quantitative results for distinguishing ⁶Li from naturally occurring lithium.

Suggest why ICP-OES does not give good quantitative results for distinguishing ⁶Li from naturally occurring lithium.

At very low temperatures, lithium atoms enhance the phonon binding of electrons in graphene suggesting the formation of Cooper pairs.

Explain how Cooper pairs are formed.

At very low temperatures, lithium atoms enhance the phonon binding of electrons in graphene suggesting the formation of Cooper pairs.

Explain how Cooper pairs are formed.

At very low temperatures, lithium atoms enhance the phonon binding of electrons in graphene suggesting the formation of Cooper pairs.

Explain how Cooper pairs are formed.

Calculate the energy released, in kJ g⁻¹, when 3.49 g of starch are completely combusted in a calorimeter, increasing the temperature of 975 g of water from 21.0 °C to 36.0 °C. Use section 1 of the data booklet.

Calculate the energy released, in kJ g⁻¹, when 3.49 g of starch are completely combusted in a calorimeter, increasing the temperature of 975 g of water from 21.0 °C to 36.0 °C. Use section 1 of the data booklet.

Calculate the energy released, in kJ g⁻¹, when 3.49 g of starch are completely combusted in a calorimeter, increasing the temperature of 975 g of water from 21.0 °C to 36.0 °C. Use section 1 of the data booklet.

The absorption spectrum of β-carotene is shown below.

Explain its colour in terms of its absorption bands. Use section 17 of the data booklet.

The absorption spectrum of β-carotene is shown below.

Explain its colour in terms of its absorption bands. Use section 17 of the data booklet.

The absorption spectrum of β-carotene is shown below.

Explain its colour in terms of its absorption bands. Use section 17 of the data booklet.

Label with an asterisk, *, the chiral carbon atom.

Label with an asterisk, *, the chiral carbon atom.

Label with an asterisk, *, the chiral carbon atom.

Explain how opiates act to provide pain relief.

Explain how opiates act to provide pain relief.

Explain how opiates act to provide pain relief.

Explain how entropy affects this equilibrium.

Explain how entropy affects this equilibrium.

Explain how entropy affects this equilibrium.

Explain the action of metals as heterogeneous catalysts.

Explain the action of metals as heterogeneous catalysts.

Explain the action of metals as heterogeneous catalysts.

Anti-HIV drugs, such as zidovudine, often become less effective over time.

Explain the development of resistant virus strains in the presence of antiviral drugs.

Anti-HIV drugs, such as zidovudine, often become less effective over time.

Explain the development of resistant virus strains in the presence of antiviral drugs.

Anti-HIV drugs, such as zidovudine, often become less effective over time.

Explain the development of resistant virus strains in the presence of antiviral drugs.

The absorption spectrum of chlorophyll a is shown below.

Suggest how the combination of chlorophyll a and carotenoids is beneficial for photosynthesis.

The absorption spectrum of chlorophyll a is shown below.

Suggest how the combination of chlorophyll a and carotenoids is beneficial for photosynthesis.

The absorption spectrum of chlorophyll a is shown below.

Suggest how the combination of chlorophyll a and carotenoids is beneficial for photosynthesis.

Draw a circle around the functional group that can be converted to the carboxylate by hydrolysis.

Draw a circle around the functional group that can be converted to the carboxylate by hydrolysis.

Draw a circle around the functional group that can be converted to the carboxylate by hydrolysis.

Identify the splitting pattern of signals X and Y.

X:

Y:

Identify the splitting pattern of signals X and Y.

X:

Y:

Identify the splitting pattern of signals X and Y.

X:

Y:

Identify the chiral carbon atom using an asterisk, *.

Identify the chiral carbon atom using an asterisk, *.

Identify the chiral carbon atom using an asterisk, *.

The melting points of cocoa butter and coconut oil are 34 °C and 25 °C respectively.

Explain this in terms of their saturated fatty acid composition.

The melting points of cocoa butter and coconut oil are 34 °C and 25 °C respectively.

Explain this in terms of their saturated fatty acid composition.

The melting points of cocoa butter and coconut oil are 34 °C and 25 °C respectively.

Explain this in terms of their saturated fatty acid composition.

Outline what is meant by genetically modified organisms.

Outline what is meant by genetically modified organisms.

Outline what is meant by genetically modified organisms.

Calculate the maximum electric energy output, in MJ, which can be obtained from burning 1.00 kg of methane by using your answer from (a).

Calculate the maximum electric energy output, in MJ, which can be obtained from burning 1.00 kg of methane by using your answer from (a).

Calculate the maximum electric energy output, in MJ, which can be obtained from burning 1.00 kg of methane by using your answer from (a).

Hydroelectric power plants produced 16% of the world’s energy in 2015, down from 21% in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Hydroelectric power plants produced 16% of the world’s energy in 2015, down from 21% in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Hydroelectric power plants produced 16% of the world’s energy in 2015, down from 21% in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Ethanol can be used in a direct-ethanol fuel cell (DEFC) as illustrated by the flow chart.

Deduce the half-equations occurring at electrodes A and B.

Electrode A: 

Electrode B:

Ethanol can be used in a direct-ethanol fuel cell (DEFC) as illustrated by the flow chart.

Deduce the half-equations occurring at electrodes A and B.

Electrode A: 

Electrode B:

Ethanol can be used in a direct-ethanol fuel cell (DEFC) as illustrated by the flow chart.

Deduce the half-equations occurring at electrodes A and B.

Electrode A: 

Electrode B:

Suggest a reason for using a phosphate salt of oseltamivir in oral tablets.

Suggest a reason for using a phosphate salt of oseltamivir in oral tablets.

Suggest a reason for using a phosphate salt of oseltamivir in oral tablets.

Enantiomers can be identified using a polarimeter. Outline how this instrument differentiates the enantiomers.

Enantiomers can be identified using a polarimeter. Outline how this instrument differentiates the enantiomers.

Enantiomers can be identified using a polarimeter. Outline how this instrument differentiates the enantiomers.

Formulate the equation for the complete hydrolysis of a starch molecule, (C₆H₁₀O₅)_n.

Formulate the equation for the complete hydrolysis of a starch molecule, (C₆H₁₀O₅)_n.

Formulate the equation for the complete hydrolysis of a starch molecule, (C₆H₁₀O₅)_n.

The addition of partially hydrogenated cocoa butter to chocolate increases its melting point and the content of trans-fatty acids (trans-fats).

Outline one effect of trans-fatty acids on health.

The addition of partially hydrogenated cocoa butter to chocolate increases its melting point and the content of trans-fatty acids (trans-fats).

Outline one effect of trans-fatty acids on health.

The addition of partially hydrogenated cocoa butter to chocolate increases its melting point and the content of trans-fatty acids (trans-fats).

Outline one effect of trans-fatty acids on health.

Explain how methane absorbs infrared (IR) radiation by referring to its molecular geometry and dipole moment.

Explain how methane absorbs infrared (IR) radiation by referring to its molecular geometry and dipole moment.

Explain how methane absorbs infrared (IR) radiation by referring to its molecular geometry and dipole moment.

Biodiesel containing ethanol can be made from renewable resources.

Suggest one environmental disadvantage of producing biodiesel from renewable resources.

Biodiesel containing ethanol can be made from renewable resources.

Suggest one environmental disadvantage of producing biodiesel from renewable resources.

Biodiesel containing ethanol can be made from renewable resources.

Suggest one environmental disadvantage of producing biodiesel from renewable resources.

Some solar cells use photovoltaic semi-conductors. Compare, giving reasons, the electrical conductivity of metals and semi-conductors as temperature increases.

Some solar cells use photovoltaic semi-conductors. Compare, giving reasons, the electrical conductivity of metals and semi-conductors as temperature increases.

Some solar cells use photovoltaic semi-conductors. Compare, giving reasons, the electrical conductivity of metals and semi-conductors as temperature increases.

Deduce the protons responsible for signals X and Y by marking them on the structure of aspirin in (a). Use section 27 of the data booklet.

Deduce the protons responsible for signals X and Y by marking them on the structure of aspirin in (a). Use section 27 of the data booklet.

Deduce the protons responsible for signals X and Y by marking them on the structure of aspirin in (a). Use section 27 of the data booklet.

Outline the disposal of LLW.

Outline the disposal of LLW.

Outline the disposal of LLW.

Magnetic resonance imaging (MRI) is an application of NMR technology using radiowaves.

Suggest why MRI is much less dangerous than imaging techniques such as X-rays and radiotracers. Use section 3 of the data booklet.

Magnetic resonance imaging (MRI) is an application of NMR technology using radiowaves.

Suggest why MRI is much less dangerous than imaging techniques such as X-rays and radiotracers. Use section 3 of the data booklet.

Magnetic resonance imaging (MRI) is an application of NMR technology using radiowaves.

Suggest why MRI is much less dangerous than imaging techniques such as X-rays and radiotracers. Use section 3 of the data booklet.

Describe the characteristics of the nematic liquid crystal phase.

Shape of molecules:

Distribution: 

Describe the characteristics of the nematic liquid crystal phase.

Shape of molecules:

Distribution: 

The critical mass for weapons-grade uranium can be as small as 15 kg. Outline what is meant by critical mass by referring to the equation in (a)(i).

The critical mass for weapons-grade uranium can be as small as 15 kg. Outline what is meant by critical mass by referring to the equation in (a)(i).

The critical mass for weapons-grade uranium can be as small as 15 kg. Outline what is meant by critical mass by referring to the equation in (a)(i).

State the name and function of X in the diagram in (b)(i).

Name:

Function:

State the name and function of X in the diagram in (b)(i).

Name:

Function:

State the name and function of X in the diagram in (b)(i).

Name:

Function:

Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.

Name the functional group and identify the absorption band that diff erentiates salicylic acid from aspirin. Use section 26 of the data booklet.

Name:

Absorption band:

Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.

Name the functional group and identify the absorption band that diff erentiates salicylic acid from aspirin. Use section 26 of the data booklet.

Name:

Absorption band:

Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.

Name the functional group and identify the absorption band that diff erentiates salicylic acid from aspirin. Use section 26 of the data booklet.

Name:

Absorption band:

Determine the percentage of technetium-99m remaining after 24.0 hours.

Determine the percentage of technetium-99m remaining after 24.0 hours.

Determine the percentage of technetium-99m remaining after 24.0 hours.

Calculate the specific energy of methane, in MJ kg⁻¹, using sections 1, 6 and 13 of the data booklet.

Calculate the specific energy of methane, in MJ kg⁻¹, using sections 1, 6 and 13 of the data booklet.

Calculate the specific energy of methane, in MJ kg⁻¹, using sections 1, 6 and 13 of the data booklet.

List the following products, which are also obtained by fractional distillation, according to decreasing volatility: asphalt, diesel, gasoline, lubricating motor oil.

List the following products, which are also obtained by fractional distillation, according to decreasing volatility: asphalt, diesel, gasoline, lubricating motor oil.

List the following products, which are also obtained by fractional distillation, according to decreasing volatility: asphalt, diesel, gasoline, lubricating motor oil.

The daughter product, ⁸⁹Kr, has a half-life of 3.15 min.

Calculate the time required, in minutes, for its radioactivity to fall to 10% of its initial value, using section 1 of the data booklet.

The daughter product, ⁸⁹Kr, has a half-life of 3.15 min.

Calculate the time required, in minutes, for its radioactivity to fall to 10% of its initial value, using section 1 of the data booklet.

The daughter product, ⁸⁹Kr, has a half-life of 3.15 min.

Calculate the time required, in minutes, for its radioactivity to fall to 10% of its initial value, using section 1 of the data booklet.

The resulting active metabolite of oseltamivir can be detected by mass spectrometry (MS) analysis.

Deduce the mass of the expected carboxylate ion.

M_r oseltamivir = 312

The resulting active metabolite of oseltamivir can be detected by mass spectrometry (MS) analysis.

Deduce the mass of the expected carboxylate ion.

M_r oseltamivir = 312

The resulting active metabolite of oseltamivir can be detected by mass spectrometry (MS) analysis.

Deduce the mass of the expected carboxylate ion.

M_r oseltamivir = 312

Outline which pK_a value should be used when calculating the pH of the solution, giving your reason.

Outline which pK_a value should be used when calculating the pH of the solution, giving your reason.

Outline which pK_a value should be used when calculating the pH of the solution, giving your reason.

Outline why the complex formed between Fe²⁺ and oxygen is red. Refer to the diagram above and section 17 of the data booklet.

Outline why the complex formed between Fe²⁺ and oxygen is red. Refer to the diagram above and section 17 of the data booklet.

Outline why the complex formed between Fe²⁺ and oxygen is red. Refer to the diagram above and section 17 of the data booklet.

Outline one advantage of allowing all countries access to the technology to generate electricity by nuclear fission.

Outline one advantage of allowing all countries access to the technology to generate electricity by nuclear fission.

Outline one advantage of allowing all countries access to the technology to generate electricity by nuclear fission.

Determine the percentage purity of the synthesized aspirin.

Determine the percentage purity of the synthesized aspirin.

Determine the percentage purity of the synthesized aspirin.

Suggest one advantage of a dye-sensitized solar cell (DSSC) over a silicon based photovoltaic cell.

Suggest one advantage of a dye-sensitized solar cell (DSSC) over a silicon based photovoltaic cell.

Suggest one advantage of a dye-sensitized solar cell (DSSC) over a silicon based photovoltaic cell.

Identify the feature in penicillin responsible for its antibiotic activity.

Identify the feature in penicillin responsible for its antibiotic activity.

Identify the feature in penicillin responsible for its antibiotic activity.

The widespread use of penicillin and its derivatives has led to the appearance of resistant S. aureus strains.

Outline how these bacteria inactivate the antibiotics.

The widespread use of penicillin and its derivatives has led to the appearance of resistant S. aureus strains.

Outline how these bacteria inactivate the antibiotics.

The widespread use of penicillin and its derivatives has led to the appearance of resistant S. aureus strains.

Outline how these bacteria inactivate the antibiotics.

Outline how the structure of penicillin has been modified to overcome this resistance.

Outline how the structure of penicillin has been modified to overcome this resistance.

Outline how the structure of penicillin has been modified to overcome this resistance.

Suggest two reasons why oil decomposes faster at the surface of the ocean than at greater depth.

Suggest two reasons why oil decomposes faster at the surface of the ocean than at greater depth.

Suggest two reasons why oil decomposes faster at the surface of the ocean than at greater depth.

Write the nuclear equation for this fission reaction.

Write the nuclear equation for this fission reaction.

Write the nuclear equation for this fission reaction.

Acid secretion can be regulated by other types of drugs such as omeprazole and ranitidine. Outline how each of these drugs acts to reduce excess stomach acid.

Omeprazole:

Ranitidine:

Acid secretion can be regulated by other types of drugs such as omeprazole and ranitidine. Outline how each of these drugs acts to reduce excess stomach acid.

Omeprazole:

Ranitidine:

Acid secretion can be regulated by other types of drugs such as omeprazole and ranitidine. Outline how each of these drugs acts to reduce excess stomach acid.

Omeprazole:

Ranitidine:

This question is about biofuel.

Evaluate the use of biodiesel in place of diesel from crude oil.

This question is about biofuel.

Evaluate the use of biodiesel in place of diesel from crude oil.

Outline how a microbial fuel cell produces an electric current from glucose.

C₆H₁₂O₆ (aq) + 6O₂ (g) → 6CO₂ (g) + 6H₂O (l)

Outline how a microbial fuel cell produces an electric current from glucose.

C₆H₁₂O₆ (aq) + 6O₂ (g) → 6CO₂ (g) + 6H₂O (l)

Outline how a microbial fuel cell produces an electric current from glucose.

C₆H₁₂O₆ (aq) + 6O₂ (g) → 6CO₂ (g) + 6H₂O (l)

Sketch graphs to show the general effect of increasing temperature on the electrical conductivity of semiconductors and metals on the axes below.

Sketch graphs to show the general effect of increasing temperature on the electrical conductivity of semiconductors and metals on the axes below.

Sketch graphs to show the general effect of increasing temperature on the electrical conductivity of semiconductors and metals on the axes below.

Lecithin aids the body’s absorption of vitamin E.

Suggest why vitamin E is fat-soluble.

Lecithin aids the body’s absorption of vitamin E.

Suggest why vitamin E is fat-soluble.

Lecithin aids the body’s absorption of vitamin E.

Suggest why vitamin E is fat-soluble.

Crude oil can be converted into fuels by fractional distillation and cracking.

Contrast these two processes.

Crude oil can be converted into fuels by fractional distillation and cracking.

Contrast these two processes.

Crude oil can be converted into fuels by fractional distillation and cracking.

Contrast these two processes.

Outline how aspirin can be chemically modified to increase its solubility in water.

Outline how aspirin can be chemically modified to increase its solubility in water.

Outline how aspirin can be chemically modified to increase its solubility in water.

Draw the full structural formula of the organic functional group formed during the polymerization of the two reactants below.

Draw the full structural formula of the organic functional group formed during the polymerization of the two reactants below.

Draw the full structural formula of the organic functional group formed during the polymerization of the two reactants below.

Explain why diamorphine (heroin) is more potent than morphine using section 37 of the data booklet.

Explain why diamorphine (heroin) is more potent than morphine using section 37 of the data booklet.

Explain why diamorphine (heroin) is more potent than morphine using section 37 of the data booklet.

Examine the synthesis of taxol in terms of green chemistry criteria.

Examine the synthesis of taxol in terms of green chemistry criteria.

Examine the synthesis of taxol in terms of green chemistry criteria.

Describe how a fuel cell breathalyser works.

Describe how a fuel cell breathalyser works.

Describe how a fuel cell breathalyser works.

Outline how alloys conduct electricity and why they are often harder than pure metals.

Conduct electricity:

Harder than pure metals:

Outline how alloys conduct electricity and why they are often harder than pure metals.

Conduct electricity:

Harder than pure metals:

Outline how alloys conduct electricity and why they are often harder than pure metals.

Conduct electricity:

Harder than pure metals:

Suggest why the addition of plasticizers is controversial.

Suggest why the addition of plasticizers is controversial.

Suggest why the addition of plasticizers is controversial.

Evaluate the suitability of technetium-99m for this use.

Evaluate the suitability of technetium-99m for this use.

Evaluate the suitability of technetium-99m for this use.

Calculate the percentage of technetium-99m remaining after 10.0 hours. Use section 1 of the data booklet.

Calculate the percentage of technetium-99m remaining after 10.0 hours. Use section 1 of the data booklet.

Calculate the percentage of technetium-99m remaining after 10.0 hours. Use section 1 of the data booklet.

Determine the mass of aluminium, in g, that could be extracted from an appropriate solution by a charge of 48 250 C. Use sections 2 and 6 of the data booklet.

Determine the mass of aluminium, in g, that could be extracted from an appropriate solution by a charge of 48 250 C. Use sections 2 and 6 of the data booklet.

Determine the mass of aluminium, in g, that could be extracted from an appropriate solution by a charge of 48 250 C. Use sections 2 and 6 of the data booklet.

Compare and contrast the bonding responsible for the two secondary structures.

One similarity:

One difference:

Compare and contrast the bonding responsible for the two secondary structures.

One similarity:

One difference:

Compare and contrast the bonding responsible for the two secondary structures.

One similarity:

One difference:

State the name of the functional group forming part of the ring structure of each monosaccharide unit.

State the name of the functional group forming part of the ring structure of each monosaccharide unit.

State the name of the functional group forming part of the ring structure of each monosaccharide unit.

Sketch the cyclic structures of the two monosaccharides which combine to form sucrose.

Sketch the cyclic structures of the two monosaccharides which combine to form sucrose.

Sketch the cyclic structures of the two monosaccharides which combine to form sucrose.

Hydrocarbons need treatment to increase their octane number to prevent pre-ignition (knocking) before they can be used in internal combustion engines.

Describe how this is carried out and the molecular changes that take place.

Hydrocarbons need treatment to increase their octane number to prevent pre-ignition (knocking) before they can be used in internal combustion engines.

Describe how this is carried out and the molecular changes that take place.

Hydrocarbons need treatment to increase their octane number to prevent pre-ignition (knocking) before they can be used in internal combustion engines.

Describe how this is carried out and the molecular changes that take place.

Calculate the half-life of an isotope whose mass falls from 5.0 × 10⁻⁵ g to 4.0 × 10⁻⁵ g in 31.4 s, using section 1 of the data booklet.

Calculate the half-life of an isotope whose mass falls from 5.0 × 10⁻⁵ g to 4.0 × 10⁻⁵ g in 31.4 s, using section 1 of the data booklet.

Calculate the half-life of an isotope whose mass falls from 5.0 × 10⁻⁵ g to 4.0 × 10⁻⁵ g in 31.4 s, using section 1 of the data booklet.

The cell potential for the spontaneous reaction when standard magnesium and silver half-cells are connected is +3.17 V.

Determine the cell potential at 298 K when:

     [Mg²⁺] = 0.0500 mol dm⁻³
     [Ag⁺] = 0.100 mol dm⁻³

Use sections 1 and 2 of the data booklet.

The cell potential for the spontaneous reaction when standard magnesium and silver half-cells are connected is +3.17 V.

Determine the cell potential at 298 K when:

     [Mg²⁺] = 0.0500 mol dm⁻³
     [Ag⁺] = 0.100 mol dm⁻³

Use sections 1 and 2 of the data booklet.

The cell potential for the spontaneous reaction when standard magnesium and silver half-cells are connected is +3.17 V.

Determine the cell potential at 298 K when:

     [Mg²⁺] = 0.0500 mol dm⁻³
     [Ag⁺] = 0.100 mol dm⁻³

Use sections 1 and 2 of the data booklet.

Some antacids contain carbonates.

Determine the pH of a buffer solution which contains 0.160 mol dm⁻³ CO₃²⁻ and 0.200 mol dm⁻³ HCO₃⁻, using section 1 of the data booklet.

pK_a (HCO₃⁻) = 10.32

Some antacids contain carbonates.

Determine the pH of a buffer solution which contains 0.160 mol dm⁻³ CO₃²⁻ and 0.200 mol dm⁻³ HCO₃⁻, using section 1 of the data booklet.

pK_a (HCO₃⁻) = 10.32

Some antacids contain carbonates.

Determine the pH of a buffer solution which contains 0.160 mol dm⁻³ CO₃²⁻ and 0.200 mol dm⁻³ HCO₃⁻, using section 1 of the data booklet.

pK_a (HCO₃⁻) = 10.32

Discuss two difficulties associated with solving the AIDS problem.

Discuss two difficulties associated with solving the AIDS problem.

Discuss two difficulties associated with solving the AIDS problem.

State and explain how a competitive inhibitor affects the maximum rate, V_max, of an enzyme-catalyzed reaction.

State and explain how a competitive inhibitor affects the maximum rate, V_max, of an enzyme-catalyzed reaction.

State and explain how a competitive inhibitor affects the maximum rate, V_max, of an enzyme-catalyzed reaction.

Describe what is meant by the genetic code and how it relates to protein synthesis.

Describe what is meant by the genetic code and how it relates to protein synthesis.

Describe what is meant by the genetic code and how it relates to protein synthesis.

Predict one absorption band present in an infrared (IR) spectrum of aspirin, using section 26 of the data booklet.

Predict one absorption band present in an infrared (IR) spectrum of aspirin, using section 26 of the data booklet.

Predict one absorption band present in an infrared (IR) spectrum of aspirin, using section 26 of the data booklet.

Determine the mass of aspirin which reacted with 16.25 cm³ of 0.100 mol dm⁻³ NaOH solution.

Determine the mass of aspirin which reacted with 16.25 cm³ of 0.100 mol dm⁻³ NaOH solution.

Determine the mass of aspirin which reacted with 16.25 cm³ of 0.100 mol dm⁻³ NaOH solution.

Determine the specific energy, in kJ g⁻¹, and energy density, in kJ cm⁻³, of hexane, C₆H₁₄. Give both answers to three significant figures.

Hexane: M_r = 86.2; ΔH_c = −4163 kJ mol⁻¹; density = 0.660 g cm⁻³

Specific energy:

Energy density:

Determine the specific energy, in kJ g⁻¹, and energy density, in kJ cm⁻³, of hexane, C₆H₁₄. Give both answers to three significant figures.

Hexane: M_r = 86.2; ΔH_c = −4163 kJ mol⁻¹; density = 0.660 g cm⁻³

Specific energy:

Energy density:

Determine the specific energy, in kJ g⁻¹, and energy density, in kJ cm⁻³, of hexane, C₆H₁₄. Give both answers to three significant figures.

Hexane: M_r = 86.2; ΔH_c = −4163 kJ mol⁻¹; density = 0.660 g cm⁻³

Specific energy:

Energy density:

Outline one approach to controlling industrial emissions of carbon dioxide.

Outline one approach to controlling industrial emissions of carbon dioxide.

Outline one approach to controlling industrial emissions of carbon dioxide.

Outline how ranitidine (Zantac) inhibits stomach acid production.

Outline how ranitidine (Zantac) inhibits stomach acid production.

Outline how ranitidine (Zantac) inhibits stomach acid production.

Outline two advantages of taking ranitidine instead of an antacid which neutralizes excess acid.

Outline two advantages of taking ranitidine instead of an antacid which neutralizes excess acid.

Outline two advantages of taking ranitidine instead of an antacid which neutralizes excess acid.

Outline why heavy metals are toxic.

Outline why heavy metals are toxic.

Outline why heavy metals are toxic.

Determine the maximum concentration of lead(II) ions at 298 K in a solution in which the concentration of carbonate ions is maintained at 1.10 × 10⁻⁴ mol dm⁻³. Use section 32 of the data booklet.

Determine the maximum concentration of lead(II) ions at 298 K in a solution in which the concentration of carbonate ions is maintained at 1.10 × 10⁻⁴ mol dm⁻³. Use section 32 of the data booklet.

Determine the maximum concentration of lead(II) ions at 298 K in a solution in which the concentration of carbonate ions is maintained at 1.10 × 10⁻⁴ mol dm⁻³. Use section 32 of the data booklet.

Explain the shape of the curve.

Explain the shape of the curve.

Explain the shape of the curve.

Outline the operation of a polarimeter used to distinguish between enantiomers.

Outline the operation of a polarimeter used to distinguish between enantiomers.

Outline the operation of a polarimeter used to distinguish between enantiomers.

Determine the other product of the fission reaction of plutonium-239.

$${}_{94}^{239}\text{Pu + }{}_0^1\text{n}\to {}_{54}^{134}\text{Xe + }.................{\text{ + 3}}_0^1\text{n}$$

Determine the other product of the fission reaction of plutonium-239.

$${}_{94}^{239}\text{Pu + }{}_0^1\text{n}\to {}_{54}^{134}\text{Xe + }.................{\text{ + 3}}_0^1\text{n}$$

Determine the other product of the fission reaction of plutonium-239.

$${}_{94}^{239}\text{Pu + }{}_0^1\text{n}\to {}_{54}^{134}\text{Xe + }.................{\text{ + 3}}_0^1\text{n}$$

Distinguish between therapeutic window and therapeutic index in humans.

Therapeutic window:

Therapeutic index:

Distinguish between therapeutic window and therapeutic index in humans.

Therapeutic window:

Therapeutic index:

Distinguish between therapeutic window and therapeutic index in humans.

Therapeutic window:

Therapeutic index:

Oil spills can be treated with an enzyme mixture to speed up decomposition.

Outline one factor to be considered when assessing the greenness of an enzyme mixture.

Oil spills can be treated with an enzyme mixture to speed up decomposition.

Outline one factor to be considered when assessing the greenness of an enzyme mixture.

Oil spills can be treated with an enzyme mixture to speed up decomposition.

Outline one factor to be considered when assessing the greenness of an enzyme mixture.

The regular rise and fall of sea levels, known as tides, can be used to generate energy.

State one advantage, other than limiting greenhouse gas emissions, and one disadvantage of tidal power.

Advantage:

Disadvantage:

The regular rise and fall of sea levels, known as tides, can be used to generate energy.

State one advantage, other than limiting greenhouse gas emissions, and one disadvantage of tidal power.

Advantage:

Disadvantage:

Outline the concept of critical mass with respect to fission reactions.

Outline the concept of critical mass with respect to fission reactions.

Outline the concept of critical mass with respect to fission reactions.

Explain the function of dyes in a dye-sensitized solar cell (DSSC).

Explain the function of dyes in a dye-sensitized solar cell (DSSC).

Explain the function of dyes in a dye-sensitized solar cell (DSSC).

State one advantage of using fusion reactions rather than fission to generate electrical power.

State one advantage of using fusion reactions rather than fission to generate electrical power.

State one advantage of using fusion reactions rather than fission to generate electrical power.

Outline how the energy of a fission reaction can be calculated.

Outline how the energy of a fission reaction can be calculated.

Outline how the energy of a fission reaction can be calculated.

Describe the effect of infrared (IR) radiation on carbon dioxide molecules.

Describe the effect of infrared (IR) radiation on carbon dioxide molecules.

Describe the effect of infrared (IR) radiation on carbon dioxide molecules.

Alcohol levels in the breath can also be determined using IR spectroscopy.

Suggest, giving a reason, which bond’s absorbance is most useful for detecting ethanol in breath.

Bond: 

Reason:

Alcohol levels in the breath can also be determined using IR spectroscopy.

Suggest, giving a reason, which bond’s absorbance is most useful for detecting ethanol in breath.

Bond: 

Reason:

Alcohol levels in the breath can also be determined using IR spectroscopy.

Suggest, giving a reason, which bond’s absorbance is most useful for detecting ethanol in breath.

Bond: 

Reason:

Hydroelectric power plants produced 16 % of the world’s energy in 2015, down from 21 % in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Hydroelectric power plants produced 16 % of the world’s energy in 2015, down from 21 % in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Hydroelectric power plants produced 16 % of the world’s energy in 2015, down from 21 % in 1971.

Suggest why hydroelectric power production has a higher efficiency than the other sources given in (b) and why its relative use has decreased despite the high efficiency.

Reason for higher efficiency:

Reason for decreased use:

Draw a circle around the functional group formed between the amino acids and state its name.

Name: 

Draw a circle around the functional group formed between the amino acids and state its name.

Name: 

Draw a circle around the functional group formed between the amino acids and state its name.

Name: 

Methane can also be obtained by fractional distillation of crude oil.

Draw a circle on the diagram to show where the methane fraction is withdrawn.

Methane can also be obtained by fractional distillation of crude oil.

Draw a circle on the diagram to show where the methane fraction is withdrawn.

Methane can also be obtained by fractional distillation of crude oil.

Draw a circle on the diagram to show where the methane fraction is withdrawn.

Suggest one application for carbon nanotubes.

Suggest one application for carbon nanotubes.

Suggest one application for carbon nanotubes.

Aspirin can be obtained from salicylic acid.

Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.

Name the functional group and identify the absorption band that differentiates salicylic acid from aspirin. Use section 26 of the data booklet.

Name: 

Absorption band:

Aspirin can be obtained from salicylic acid.

Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.

Name the functional group and identify the absorption band that differentiates salicylic acid from aspirin. Use section 26 of the data booklet.

Name: 

Absorption band:

Outline the disposal of LLW.

Outline the disposal of LLW.