Topic 11: Measurement and data processing

A student obtained the following data to calculate $q$, using $q=mc\mathrm{\Delta }T$.

$m=20.2 \mathrm{g}\pm 0.2 \mathrm{g}$

$∆T=10°\mathrm{C}\pm 1°\mathrm{C}$

$c=4.18 \mathrm{J} {\mathrm{g}}^{-1} {\mathrm{K}}^{-1}$

What is the percentage uncertainty in the calculated value of $q$?

A.  $0.2$

B.  $1.2$

C.  $11$

D.  $14$

A student obtained the following data to calculate $q$, using $q=mc\mathrm{\Delta }T$.

$m=20.2 \mathrm{g}\pm 0.2 \mathrm{g}$

$∆T=10°\mathrm{C}\pm 1°\mathrm{C}$

$c=4.18 \mathrm{J} {\mathrm{g}}^{-1} {\mathrm{K}}^{-1}$

What is the percentage uncertainty in the calculated value of $q$?

A.  $0.2$

B.  $1.2$

C.  $11$

D.  $14$

What is the index of hydrogen deficiency (IHD) in cyclohexanol?

A.  $0$

B.  $1$

C.  $2$

D.  $3$

What is the index of hydrogen deficiency (IHD) in cyclohexanol?

A.  $0$

B.  $1$

C.  $2$

D.  $3$

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

Potassium hydroxide solutions can react with carbon dioxide from the air. The solution was made one day prior to using it in the titration.

Predict, giving a reason, the effect of this error on the calculated concentration of ethanoic acid in 5(e).

Potassium hydroxide solutions can react with carbon dioxide from the air. The solution was made one day prior to using it in the titration.

Predict, giving a reason, the effect of this error on the calculated concentration of ethanoic acid in 5(e).

Potassium hydroxide solutions can react with carbon dioxide from the air. The solution was made one day prior to using it in the titration.

Predict, giving a reason, the effect of this error on the calculated concentration of ethanoic acid in 5(e).

Deduce the number of signals and chemical shifts with splitting patterns in the ¹H NMR spectrum of ethoxyethane. Use section 27 of the data booklet.

Deduce the number of signals and chemical shifts with splitting patterns in the ¹H NMR spectrum of ethoxyethane. Use section 27 of the data booklet.

Deduce the number of signals and chemical shifts with splitting patterns in the ¹H NMR spectrum of ethoxyethane. Use section 27 of the data booklet.

What information is provided by ¹H NMR, MS and IR for an organic compound?

I.   ¹H NMR: chemical environment(s) of protons
II.  MS: fragmentation pattern
III. IR: types of functional group

A. I and II only

B. I and III only

C. II and III only

D. I, II and III

What information is provided by ¹H NMR, MS and IR for an organic compound?

I.   ¹H NMR: chemical environment(s) of protons
II.  MS: fragmentation pattern
III. IR: types of functional group

A. I and II only

B. I and III only

C. II and III only

D. I, II and III

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.

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.

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

Calculate the uncertainty in the change in pH.

Calculate the uncertainty in the change in pH.

Calculate the uncertainty in the change in pH.

Determine the index of hydrogen deficiency (IHD) of paracetamol.

A.  3

B.  4

C.  5

D.  6

Determine the index of hydrogen deficiency (IHD) of paracetamol.

A.  3

B.  4

C.  5

D.  6

Deduce the relationship between the concentration of N₂O₅ and the rate of reaction.

Deduce the relationship between the concentration of N₂O₅ and the rate of reaction.

Deduce the relationship between the concentration of N₂O₅ and the rate of reaction.

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Deduce the identity of the unknown compound using the previous information, the ¹H NMR spectrum and section 27 of the data booklet.

SDBS, National Institute of Advanced Industrial Science and Technology (AIST).

Predict from your line of best fit the rate of reaction when the concentration of HCl is 1.00 mol dm⁻³.

Predict from your line of best fit the rate of reaction when the concentration of HCl is 1.00 mol dm⁻³.

Predict from your line of best fit the rate of reaction when the concentration of HCl is 1.00 mol dm⁻³.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

Predict the number of signals in the ¹H NMR spectrum of urea.

Predict the number of signals in the ¹H NMR spectrum of urea.

Predict the number of signals in the ¹H NMR spectrum of urea.

Draw the best fit line for the reaction excluding point D.

Draw the best fit line for the reaction excluding point D.

Draw the best fit line for the reaction excluding point D.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The IR spectrum of urea is shown below.

Identify the bonds causing the absorptions at 3450 cm⁻¹ and 1700 cm⁻¹ using section 26 of the data booklet.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

The mass spectrum of urea is shown below.

Identify the species responsible for the peaks at m/z = 60 and 44.

Predict the number of signals in the ¹H NMR spectrum of urea.

Predict the number of signals in the ¹H NMR spectrum of urea.

Predict the number of signals in the ¹H NMR spectrum of urea.

Justify why it is inappropriate to record the uncertainty of the mean as ±0.01 s.

Justify why it is inappropriate to record the uncertainty of the mean as ±0.01 s.

Justify why it is inappropriate to record the uncertainty of the mean as ±0.01 s.

If doubling the concentration doubles the reaction rate, suggest the mean time you would expect for the reaction with 2.00 mol dm⁻³ hydrochloric acid.

If doubling the concentration doubles the reaction rate, suggest the mean time you would expect for the reaction with 2.00 mol dm⁻³ hydrochloric acid.

If doubling the concentration doubles the reaction rate, suggest the mean time you would expect for the reaction with 2.00 mol dm⁻³ hydrochloric acid.

Another student, working alone, always dropped the marble chips into the acid and then picked up the stopwatch to start it. State, giving a reason, whether this introduced a random or systematic error.

Another student, working alone, always dropped the marble chips into the acid and then picked up the stopwatch to start it. State, giving a reason, whether this introduced a random or systematic error.

Another student, working alone, always dropped the marble chips into the acid and then picked up the stopwatch to start it. State, giving a reason, whether this introduced a random or systematic error.

Deduce the molecular formula of the compound.

Deduce the molecular formula of the compound.

Deduce the molecular formula of the compound.

Identify the bonds causing peaks A and B in the IR spectrum of the unknown compound using section 26 of the data booklet.

Identify the bonds causing peaks A and B in the IR spectrum of the unknown compound using section 26 of the data booklet.

Identify the bonds causing peaks A and B in the IR spectrum of the unknown compound using section 26 of the data booklet.

Deduce full structural formulas of two possible isomers of the unknown compound, both of which are esters.

Deduce full structural formulas of two possible isomers of the unknown compound, both of which are esters.

Deduce full structural formulas of two possible isomers of the unknown compound, both of which are esters.

Deduce the formula of the unknown compound based on its ¹H NMR spectrum using section 27 of the data booklet.

Deduce the formula of the unknown compound based on its ¹H NMR spectrum using section 27 of the data booklet.

Deduce the formula of the unknown compound based on its ¹H NMR spectrum using section 27 of the data booklet.

Deduce the number of ¹H NMR signals produced by the zwitterion form of alanine.

Deduce the number of ¹H NMR signals produced by the zwitterion form of alanine.

Deduce the number of ¹H NMR signals produced by the zwitterion form of alanine.

The graph shows Gibbs free energy of a mixture of N₂O₄(g) and NO₂(g) in different proportions.

N₂O₄(g) $\rightleftharpoons$ 2NO₂(g)

Which point shows the system at equilibrium?

The graph shows Gibbs free energy of a mixture of N₂O₄(g) and NO₂(g) in different proportions.

N₂O₄(g) $\rightleftharpoons$ 2NO₂(g)

Which point shows the system at equilibrium?

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

Deduce the equation for the relationship between absorbance and concentration.

Deduce the equation for the relationship between absorbance and concentration.

Deduce the equation for the relationship between absorbance and concentration.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

Sketch the pH curve for the titration of 25.0 cm³ of ethylamine aqueous solution with 50.0 cm³ of butanoic acid aqueous solution of equal concentration. No calculations are required.

Sketch the pH curve for the titration of 25.0 cm³ of ethylamine aqueous solution with 50.0 cm³ of butanoic acid aqueous solution of equal concentration. No calculations are required.

Sketch the pH curve for the titration of 25.0 cm³ of ethylamine aqueous solution with 50.0 cm³ of butanoic acid aqueous solution of equal concentration. No calculations are required.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Deduce the appropriate number of significant figures for your answer in (d)(i).

Deduce the appropriate number of significant figures for your answer in (d)(i).

Deduce the appropriate number of significant figures for your answer in (d)(i).

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

Deduce the appropriate number of significant figures for your answer in (e)(i).

Deduce the appropriate number of significant figures for your answer in (e)(i).

Deduce the appropriate number of significant figures for your answer in (e)(i).

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

The original piece of brass weighed 0.200 g. The absorbance was 0.32.

Calculate, showing your working, the percentage of copper by mass in the brass.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

The only significant uncertainty is in the temperature measurement.

Determine the absolute uncertainty in the calculated value of ΔH if the uncertainty in the temperature rise was ±0.2 °C.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Sketch a graph of the concentration of iron(II) sulfate, FeSO₄, against time as the reaction proceeds.

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

Outline how the initial rate of reaction can be determined from the graph in part (c)(i).

Deduce the equation for the relationship between absorbance and concentration.

Deduce the equation for the relationship between absorbance and concentration.

Deduce the equation for the relationship between absorbance and concentration.

A student performed an experiment to find the melting point of sulfur, obtaining 118.0 °C. The literature value is 115.2 °C. What was the percentage error?

A.  $\frac{118.0-115.2}{115.2}\times 100\%$

B.  $\frac{115.2}{118.0}\times 100\%$

C.  $\frac{118.0-115.2}{118.0}\times 100\%$

D.  $\frac{118.0}{115.2}\times 100\%$

A student performed an experiment to find the melting point of sulfur, obtaining 118.0 °C. The literature value is 115.2 °C. What was the percentage error?

A.  $\frac{118.0-115.2}{115.2}\times 100\%$

B.  $\frac{115.2}{118.0}\times 100\%$

C.  $\frac{118.0-115.2}{118.0}\times 100\%$

D.  $\frac{118.0}{115.2}\times 100\%$

Which compound produces this mass spectrum?

^{[Spectral Database for Organic Compounds, SDBS. SDBS Compounds and Spectral Search. [graph] Available at:
https://sdbs.db.aist.go.jp [Accessed 3 January 2019].]}

Which compound produces this mass spectrum?

^{[Spectral Database for Organic Compounds, SDBS. SDBS Compounds and Spectral Search. [graph] Available at:
https://sdbs.db.aist.go.jp [Accessed 3 January 2019].]}

What is the index of hydrogen deficiency (IHD) of this molecule?

Paracetamol (acetaminophen)

A.  3

B.  4

C.  5

D.  6

What is the index of hydrogen deficiency (IHD) of this molecule?

Paracetamol (acetaminophen)

A.  3

B.  4

C.  5

D.  6

20 cm³ of 1 mol dm⁻³ sulfuric acid was added dropwise to 20 cm³ of 1 mol dm⁻³ barium hydroxide producing a precipitate of barium sulfate.

H₂SO₄(aq) + Ba(OH)₂(aq) → 2H₂O (l) + BaSO₄(s)

Which graph represents a plot of conductivity against volume of acid added?

20 cm³ of 1 mol dm⁻³ sulfuric acid was added dropwise to 20 cm³ of 1 mol dm⁻³ barium hydroxide producing a precipitate of barium sulfate.

H₂SO₄(aq) + Ba(OH)₂(aq) → 2H₂O (l) + BaSO₄(s)

Which graph represents a plot of conductivity against volume of acid added?

Determine the percentage uncertainty of the mass of product after heating.

Determine the percentage uncertainty of the mass of product after heating.

Determine the percentage uncertainty of the mass of product after heating.

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

Suggest two differences in the ¹H NMR of but-2-ene and the organic product from (d)(ii).

The experiment gave an error in the rate because the pressure gauge was inaccurate.

Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

The experiment gave an error in the rate because the pressure gauge was inaccurate.

Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

The experiment gave an error in the rate because the pressure gauge was inaccurate.

Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

Describe the density trend across periods 4 and 5 of the periodic table.

Describe the density trend across periods 4 and 5 of the periodic table.

Describe the density trend across periods 4 and 5 of the periodic table.

The uncertainty of the 100.0cm³ volumetric flask used to make the solution was ±0.6cm³.

Calculate the maximum percentage uncertainty in the mass of NaHCO₃ so that the concentration of the solution is correct to ±1.0 %.

The uncertainty of the 100.0cm³ volumetric flask used to make the solution was ±0.6cm³.

Calculate the maximum percentage uncertainty in the mass of NaHCO₃ so that the concentration of the solution is correct to ±1.0 %.

The uncertainty of the 100.0cm³ volumetric flask used to make the solution was ±0.6cm³.

Calculate the maximum percentage uncertainty in the mass of NaHCO₃ so that the concentration of the solution is correct to ±1.0 %.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

Identify one error associated with the use of an accurate stopwatch.

Identify one error associated with the use of an accurate stopwatch.

Identify one error associated with the use of an accurate stopwatch.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would diff er, using section 26 of the data booklet.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would diff er, using section 26 of the data booklet.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would diff er, using section 26 of the data booklet.

What can be deduced from the infrared (IR) spectrum of a compound?

A. Number of hydrogens

B. Number of hydrogen environments

C. Bonds present

D. Molar mass

What can be deduced from the infrared (IR) spectrum of a compound?

A. Number of hydrogens

B. Number of hydrogen environments

C. Bonds present

D. Molar mass

Which technique involves breaking covalent bonds when carried out on an organic compound?

A. infrared spectroscopy

B. nuclear magnetic resonance spectroscopy

C. X-ray crystallography

D. mass spectrometry

Which technique involves breaking covalent bonds when carried out on an organic compound?

A. infrared spectroscopy

B. nuclear magnetic resonance spectroscopy

C. X-ray crystallography

D. mass spectrometry

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

The IR spectrum and low resolution ¹H NMR spectrum of the actual product formed are shown.

Deduce whether the product is A or B, using evidence from these spectra together with sections 26 and 27 of the data booklet.

Identity of product:

One piece of evidence from IR:

One piece of evidence from ¹H NMR:

The IR spectrum and low resolution ¹H NMR spectrum of the actual product formed are shown.

Deduce whether the product is A or B, using evidence from these spectra together with sections 26 and 27 of the data booklet.

Identity of product:

One piece of evidence from IR:

One piece of evidence from ¹H NMR:

The IR spectrum and low resolution ¹H NMR spectrum of the actual product formed are shown.

Deduce whether the product is A or B, using evidence from these spectra together with sections 26 and 27 of the data booklet.

Identity of product:

One piece of evidence from IR:

One piece of evidence from ¹H NMR:

The experiment gave an error in the rate because the pressure gauge was inaccurate. Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

The experiment gave an error in the rate because the pressure gauge was inaccurate. Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

The experiment gave an error in the rate because the pressure gauge was inaccurate. Outline whether repeating the experiment, using the same apparatus, and averaging the results would reduce the error.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Compare the ease of oxidation of s-block and d-block metals to their melting points and densities. Use section 25 of the data booklet.

Identify one error associated with the use of an accurate stopwatch.

Identify one error associated with the use of an accurate stopwatch.

Identify one error associated with the use of an accurate stopwatch.

Data collected from a larger number of silicon samples could also be plotted to determine the density using the following axes.

Which statements are correct?

    I. The density is the slope of the graph.
    II. The data will show that mass is proportional to volume.
    III. The best-fit line should pass through the origin.

A. I and II only

B. I and III only

C. II and III only

D. I, II and III

Data collected from a larger number of silicon samples could also be plotted to determine the density using the following axes.

Which statements are correct?

    I. The density is the slope of the graph.
    II. The data will show that mass is proportional to volume.
    III. The best-fit line should pass through the origin.

A. I and II only

B. I and III only

C. II and III only

D. I, II and III

What is the degree of unsaturation (index of hydrogen deficiency) for the molecule?

A. 1

B. 2

C. 4

D. 5

What is the degree of unsaturation (index of hydrogen deficiency) for the molecule?

A. 1

B. 2

C. 4

D. 5

The dotted line represents the formation of oxygen, O₂(g), from the uncatalysed complete decomposition of hydrogen peroxide, H₂O₂ (aq).

Which curve represents a catalysed reaction under the same conditions?

The dotted line represents the formation of oxygen, O₂(g), from the uncatalysed complete decomposition of hydrogen peroxide, H₂O₂ (aq).

Which curve represents a catalysed reaction under the same conditions?

What can be deduced from the infrared (IR) spectrum of a compound?

A. Number of hydrogens

B. Number of hydrogen environments

C. Bonds present

D. Molar mass

What can be deduced from the infrared (IR) spectrum of a compound?

A. Number of hydrogens

B. Number of hydrogen environments

C. Bonds present

D. Molar mass

Calculate the percentage uncertainty of the day 5 titre.

Calculate the percentage uncertainty of the day 5 titre.

Calculate the percentage uncertainty of the day 5 titre.

Explain why the ¹H NMR spectrum of C₃H₆O, produced in (d)(i), shows only one signal.

Explain why the ¹H NMR spectrum of C₃H₆O, produced in (d)(i), shows only one signal.

Explain why the ¹H NMR spectrum of C₃H₆O, produced in (d)(i), shows only one signal.

Determine the initial rate of reaction of limestone with nitric acid from the graph.

Show your working on the graph and include the units of the initial rate.

Determine the initial rate of reaction of limestone with nitric acid from the graph.

Show your working on the graph and include the units of the initial rate.

Determine the initial rate of reaction of limestone with nitric acid from the graph.

Show your working on the graph and include the units of the initial rate.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (e)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (e)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (e)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (e)(ii).

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (e)(ii).

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (e)(ii).

If you did not obtain an answer in (e)(ii), use 6.55 g, although this is not the correct answer.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (d)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (d)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

The absolute uncertainty in mass of the contents of the cold pack is ±0.01 g and in each temperature reading is ±0.2 °C. Using your answer in (d)(ii), calculate the absolute uncertainty in the mass of ammonium nitrate in the cold pack.

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (d)(ii).

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (d)(ii).

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

The cold pack contains 9.50 g of ammonium nitrate. Calculate the percentage error in the experimentally determined mass of ammonium nitrate obtained in (d)(ii).

If you did not obtain an answer in (d)(ii), use 6.55 g, although this is not the correct answer.

Determine the index of hydrogen deficiency, IHD, of chloroquine.

Determine the index of hydrogen deficiency, IHD, of chloroquine.

Determine the index of hydrogen deficiency, IHD, of chloroquine.

State the number of ¹H NMR signals for this isomer of xylene and the ratio in which they appear.

State the number of ¹H NMR signals for this isomer of xylene and the ratio in which they appear.

State the number of ¹H NMR signals for this isomer of xylene and the ratio in which they appear.

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of
formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of
formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

In a laboratory experiment solutions of potassium iodide and hydrogen peroxide were mixed and the volume of oxygen generated was recorded. The volume was adjusted to 0 at t = 0.

The data for the first trial is given below.

Plot a graph on the axes below and from it determine the average rate of
formation of oxygen gas in cm³ O₂ (g) s⁻¹.

Average rate of reaction:

The dotted line represents the formation of oxygen, O₂ (g), from the uncatalysed complete decomposition of hydrogen peroxide, H₂O₂ (aq).

Which curve represents a catalysed reaction under the same conditions?

The dotted line represents the formation of oxygen, O₂ (g), from the uncatalysed complete decomposition of hydrogen peroxide, H₂O₂ (aq).

Which curve represents a catalysed reaction under the same conditions?

State the number of 1H NMR signals for this isomer of xylene and the ratio in which they appear.

Number of signals:

Ratio:

State the number of 1H NMR signals for this isomer of xylene and the ratio in which they appear.

Number of signals:

Ratio:

State the number of 1H NMR signals for this isomer of xylene and the ratio in which they appear.

Number of signals:

Ratio:

Describe the density trend across periods 4 and 5 of the periodic table.

Describe the density trend across periods 4 and 5 of the periodic table.

Describe the density trend across periods 4 and 5 of the periodic table.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

Describe one systematic error associated with the use of the gas syringe, and how the error affects the calculated rate.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would differ, using section 26 of the data booklet.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would differ, using section 26 of the data booklet.

The infrared (IR) spectrum of polyethene is given.

Suggest how the IR spectrum of polychloroethene would differ, using section 26 of the data booklet.

Deduce the number of signals and their chemical shifts in the ${}_1\mathrm{H} \mathrm{NMR}$ spectrum of ethoxyethane. Use section 27 of the data booklet.

Deduce the number of signals and their chemical shifts in the ${}_1\mathrm{H} \mathrm{NMR}$ spectrum of ethoxyethane. Use section 27 of the data booklet.

Deduce the number of signals and their chemical shifts in the ${}_1\mathrm{H} \mathrm{NMR}$ spectrum of ethoxyethane. Use section 27 of the data booklet.

Calculate the percentage uncertainty and percentage error in the experimentally determined value of $K_{\mathrm{c}}$ for methanol.

Calculate the percentage uncertainty and percentage error in the experimentally determined value of $K_{\mathrm{c}}$ for methanol.

Calculate the percentage uncertainty and percentage error in the experimentally determined value of $K_{\mathrm{c}}$ for methanol.

Which spectra would show the difference between propan-2-ol, CH₃CH(OH)CH₃, and propanal, CH₃CH₂CHO?

I.   mass
II.  infrared
III. ¹H NMR

A.  I and II only

B.  I and III only

C.  II and III only

D.  I, II and III

Which spectra would show the difference between propan-2-ol, CH₃CH(OH)CH₃, and propanal, CH₃CH₂CHO?

I.   mass
II.  infrared
III. ¹H NMR

A.  I and II only

B.  I and III only

C.  II and III only

D.  I, II and III

What can be deduced from the mass spectrum of CH₃COCH₂CH₂CH₃?

NIST Mass Spectrometry Data Center Collection (C) 2021 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. 2-Pentanone Mass Spectrum, MS Number 291264. [graph] Available at: https://webbook.nist.gov/cgi/cbook.cgi?ID=C107879&Units=SI&Mask=200#Mass-Spec2-pentanone [Accessed 4 May 2020]. source adapted.

A.  The molar mass is 43 g mol⁻¹.

B.  The atoms have many isotopes.

C.  The most likely bond to break is C–C between carbons 2 and 3.

D.  The signal with the largest mass is due to the oxidation of the ketone in the spectrometer.

What can be deduced from the mass spectrum of CH₃COCH₂CH₂CH₃?

NIST Mass Spectrometry Data Center Collection (C) 2021 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. 2-Pentanone Mass Spectrum, MS Number 291264. [graph] Available at: https://webbook.nist.gov/cgi/cbook.cgi?ID=C107879&Units=SI&Mask=200#Mass-Spec2-pentanone [Accessed 4 May 2020]. source adapted.

A.  The molar mass is 43 g mol⁻¹.

B.  The atoms have many isotopes.

C.  The most likely bond to break is C–C between carbons 2 and 3.

D.  The signal with the largest mass is due to the oxidation of the ketone in the spectrometer.

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

Identify each compound from the spectra given, use absorptions from the range of 1700 cm⁻¹ to 3500 cm⁻¹. Explain the reason for your choice, referring to section 26 of the data booklet.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

A student dissolved 0.1240 ± 0.0001 g of Na₂S₂O₃ to make 1000.0 ± 0.4 cm³ of solution to use in the Winkler Method.

Determine the percentage uncertainty in the molar concentration.

Given equimolar concentrations, which substance would produce the strongest signal in a ¹H NMR spectrum?

A.  (CH₃)₃CH

B.  C₆H₆

C.  C₈H₁₈

D.  Si(CH₃)₄

Given equimolar concentrations, which substance would produce the strongest signal in a ¹H NMR spectrum?

A.  (CH₃)₃CH

B.  C₆H₆

C.  C₈H₁₈

D.  Si(CH₃)₄

Determine the percentage uncertainty of the mass of product after heating.

Determine the percentage uncertainty of the mass of product after heating.

Determine the percentage uncertainty of the mass of product after heating.

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Suggest an explanation, other than product being lost from the crucible or reacting with nitrogen, that could explain the yield found in (b)(iii).

Use the graph to deduce the dependence of the reaction rate on the amount of Mg.

Use the graph to deduce the dependence of the reaction rate on the amount of Mg.

Use the graph to deduce the dependence of the reaction rate on the amount of Mg.

Carbonates also react with HCl and the rate can be determined by graphing the mass loss. Suggest why this method is less suitable for the reaction of Mg with HCl.

Carbonates also react with HCl and the rate can be determined by graphing the mass loss. Suggest why this method is less suitable for the reaction of Mg with HCl.

Carbonates also react with HCl and the rate can be determined by graphing the mass loss. Suggest why this method is less suitable for the reaction of Mg with HCl.

Suggest a reason why the volume of hydrogen gas collected was smaller than predicted.

Suggest a reason why the volume of hydrogen gas collected was smaller than predicted.

Suggest a reason why the volume of hydrogen gas collected was smaller than predicted.

State the oxidation state of sulfur in copper (II) sulfate.

State the oxidation state of sulfur in copper (II) sulfate.

State the oxidation state of sulfur in copper (II) sulfate.

State the oxidation state of sulfur in copper (II) sulfate.

State the oxidation state of sulfur in copper (II) sulfate.

State the oxidation state of sulfur in copper (II) sulfate.