5.1 Measuring energy changes

Which statement is correct for this reaction?

Fe₂O₃ (s) + 3CO (g) → 2Fe (s) + 3CO₂ (g)       ΔH = −26.6 kJ

A. 13.3 kJ are released for every mole of Fe produced.

B. 26.6 kJ are absorbed for every mole of Fe produced.

C. 53.2 kJ are released for every mole of Fe produced.

D. 26.6 kJ are released for every mole of Fe produced.

Which statement is correct for this reaction?

Fe₂O₃ (s) + 3CO (g) → 2Fe (s) + 3CO₂ (g)       ΔH = −26.6 kJ

A. 13.3 kJ are released for every mole of Fe produced.

B. 26.6 kJ are absorbed for every mole of Fe produced.

C. 53.2 kJ are released for every mole of Fe produced.

D. 26.6 kJ are released for every mole of Fe produced.

Determine the heat change, q, in kJ, for the neutralization reaction between ethanoic acid and sodium hydroxide.

Assume the specific heat capacities of the solutions and their densities are those of water.

Determine the heat change, q, in kJ, for the neutralization reaction between ethanoic acid and sodium hydroxide.

Assume the specific heat capacities of the solutions and their densities are those of water.

Determine the heat change, q, in kJ, for the neutralization reaction between ethanoic acid and sodium hydroxide.

Assume the specific heat capacities of the solutions and their densities are those of water.

What is the heat change, in kJ, when 100.0 g of aluminium is heated from 19.0 °C to 32.0 °C?

Specific heat capacity of aluminium: 0.90 J g⁻¹K⁻¹

A.  $0.90\times 100.0\times 13.0$

B.  $0.90\times 100.0\times 286$

C.  $\frac{0.90\times 100.0\times 13.0}{1000}$

D.  $\frac{0.90\times 100.0\times 286}{1000}$

What is the heat change, in kJ, when 100.0 g of aluminium is heated from 19.0 °C to 32.0 °C?

Specific heat capacity of aluminium: 0.90 J g⁻¹K⁻¹

A.  $0.90\times 100.0\times 13.0$

B.  $0.90\times 100.0\times 286$

C.  $\frac{0.90\times 100.0\times 13.0}{1000}$

D.  $\frac{0.90\times 100.0\times 286}{1000}$

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Two 100 cm³ aqueous solutions, one containing 0.010 mol NaOH and the other 0.010 mol HCl, are at the same temperature.

When the two solutions are mixed the temperature rises by y °C.

Assume the density of the final solution is 1.00 g cm⁻³.

Specific heat capacity of water = 4.18 J g⁻¹ K⁻¹

What is the enthalpy change of neutralization in kJ mol⁻¹?

A.     $\frac{200\times 4.18\times y}{1000\times 0.020}$

B.     $\frac{200\times 4.18\times y}{1000\times 0.010}$

C.     $\frac{100\times 4.18\times y}{1000\times 0.010}$

D.     $\frac{200\times 4.18\times (y+273)}{1000\times 0.010}$

Two 100 cm³ aqueous solutions, one containing 0.010 mol NaOH and the other 0.010 mol HCl, are at the same temperature.

When the two solutions are mixed the temperature rises by y °C.

Assume the density of the final solution is 1.00 g cm⁻³.

Specific heat capacity of water = 4.18 J g⁻¹ K⁻¹

What is the enthalpy change of neutralization in kJ mol⁻¹?

A.     $\frac{200\times 4.18\times y}{1000\times 0.020}$

B.     $\frac{200\times 4.18\times y}{1000\times 0.010}$

C.     $\frac{100\times 4.18\times y}{1000\times 0.010}$

D.     $\frac{200\times 4.18\times (y+273)}{1000\times 0.010}$

State another assumption you made in (b)(i).

State another assumption you made in (b)(i).

State another assumption you made in (b)(i).

Calculate the standard enthalpy change, ΔH^Θ, of step 2 using section 13 of the data booklet.

Calculate the standard enthalpy change, ΔH^Θ, of step 2 using section 13 of the data booklet.

Calculate the standard enthalpy change, ΔH^Θ, of step 2 using section 13 of the data booklet.

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

Which combination of ΔH₁, ΔH₂, and ΔH₃ would give the enthalpy of the reaction?

CS₂(l) + 3O₂(g) → CO₂(g) + 2SO₂(g)

ΔH₁  C (s) + O₂(g) → CO₂(g)
ΔH₂  S (s) + O₂(g) → SO₂(g)
ΔH₃  C (s) + 2S (s) → CS₂(l)

A.  ΔH = ΔH₁ + ΔH₂ + ΔH₃

B.  ΔH = ΔH₁ + ΔH₂ − ΔH₃

C.  ΔH = ΔH₁ + 2(ΔH₂) + ΔH₃

D.  ΔH = ΔH₁ + 2(ΔH₂) − ΔH₃

Which combination of ΔH₁, ΔH₂, and ΔH₃ would give the enthalpy of the reaction?

CS₂(l) + 3O₂(g) → CO₂(g) + 2SO₂(g)

ΔH₁  C (s) + O₂(g) → CO₂(g)
ΔH₂  S (s) + O₂(g) → SO₂(g)
ΔH₃  C (s) + 2S (s) → CS₂(l)

A.  ΔH = ΔH₁ + ΔH₂ + ΔH₃

B.  ΔH = ΔH₁ + ΔH₂ − ΔH₃

C.  ΔH = ΔH₁ + 2(ΔH₂) + ΔH₃

D.  ΔH = ΔH₁ + 2(ΔH₂) − ΔH₃

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

The change in enthalpy when ammonium nitrate dissolves in water is 25.69 kJ mol⁻¹. Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (e)(i) and section 6 of the data booklet.

If you did not obtain an answer in (e)(i), use 3.11 × 10³ J, although this is not the correct answer.

The change in enthalpy when ammonium nitrate dissolves in water is 25.69 kJ mol⁻¹. Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (e)(i) and section 6 of the data booklet.

If you did not obtain an answer in (e)(i), use 3.11 × 10³ J, although this is not the correct answer.

The change in enthalpy when ammonium nitrate dissolves in water is 25.69 kJ mol⁻¹. Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (e)(i) and section 6 of the data booklet.

If you did not obtain an answer in (e)(i), use 3.11 × 10³ J, although this is not the correct answer.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

The mass of the contents of the cold pack is 25.32 g and its initial temperature is 25.2 °C. Once the contents are mixed, the temperature drops to 0.8 °C.

Calculate the energy, in J, absorbed by the dissolution of ammonium nitrate in water within the cold pack. Assume the specific heat capacity of the solution is 4.18 J g⁻¹ K⁻¹. Use section 1 of the data booklet.

Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (d)(i) and and sections 6 and 19 of the data booklet.

If you did not obtain an answer in (d)(i), use 3.11 × 10³ J, although this is not the correct answer.

Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (d)(i) and and sections 6 and 19 of the data booklet.

If you did not obtain an answer in (d)(i), use 3.11 × 10³ J, although this is not the correct answer.

Determine the mass of ammonium nitrate in the cold pack using your answer obtained in (d)(i) and and sections 6 and 19 of the data booklet.

If you did not obtain an answer in (d)(i), use 3.11 × 10³ J, although this is not the correct answer.

The combustion of glucose is exothermic and occurs according to the following equation:

C₆H₁₂O₆ (s) + 6O₂ (g) → 6CO₂ (g) + 6H₂O (g)

Which is correct for this reaction?

The combustion of glucose is exothermic and occurs according to the following equation:

C₆H₁₂O₆ (s) + 6O₂ (g) → 6CO₂ (g) + 6H₂O (g)

Which is correct for this reaction?

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group whereas the melting points of the group 17 elements (F → I) increase down the group.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group whereas the melting points of the group 17 elements (F → I) increase down the group.

Explain why the melting points of the group 1 metals (Li → Cs) decrease down the group whereas the melting points of the group 17 elements (F → I) increase down the group.

Which is correct when Ba(OH)₂ reacts with NH₄Cl?

Ba(OH)₂ (s) + 2NH₄Cl (s) → BaCl₂ (aq) + 2NH₃ (g) + 2H₂O (l)       ΔH^Θ = +164 kJ mol⁻¹

Which is correct when Ba(OH)₂ reacts with NH₄Cl?

Ba(OH)₂ (s) + 2NH₄Cl (s) → BaCl₂ (aq) + 2NH₃ (g) + 2H₂O (l)       ΔH^Θ = +164 kJ mol⁻¹

State another assumption you made in (b)(i).

State another assumption you made in (b)(i).

State another assumption you made in (b)(i).

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

The reaction was carried out in a calorimeter. The maximum temperature rise of the solution was 7.5 °C.

Calculate the enthalpy change, ΔH, of the reaction, in kJ, assuming that all the heat released was absorbed by the solution. Use sections 1 and 2 of the data booklet.

State what point Y on the graph represents.

State what point Y on the graph represents.

State what point Y on the graph represents.

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

Estimate the time at which the powdered zinc was placed in the beaker.

Estimate the time at which the powdered zinc was placed in the beaker.

Estimate the time at which the powdered zinc was placed in the beaker.

State what point Y on the graph represents.

State what point Y on the graph represents.

State what point Y on the graph represents.

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

The maximum temperature used to calculate the enthalpy of reaction was chosen at a point on the extrapolated (dotted) line.

State the maximum temperature which should be used and outline one assumption made in choosing this temperature on the extrapolated line.

Maximum temperature:

Assumption:

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

To determine the enthalpy of reaction the experiment was carried out five times. The same volume and concentration of copper(II) sulfate was used but the mass of zinc was different each time. Suggest, with a reason, if zinc or copper(II) sulfate should be in excess for each trial.

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

The formula q = mcΔT was used to calculate the energy released. The values used in the calculation were m = 25.00 g, c = 4.18 J g⁻¹ K⁻¹.

State an assumption made when using these values for m and c.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.

What is the enthalpy of combustion, ΔH_c, of ethanol in kJ mol⁻¹?
Maximum temperature of water: 30.0°C
Initial temperature of water: 20.0°C
Mass of water in beaker: 100.0 g
Loss in mass of ethanol: 0.230 g
M_r (ethanol): 46.08
Specific heat capacity of water: 4.18 J g⁻¹ K⁻¹
q = mcΔT

A.  $-\frac{100.0\times 4.18\times (10.0\times 273)}{{\displaystyle \frac{0.230}{46.08}}\times 1000}$

B.  $-\frac{0.0230\times 4.18\times 10.0}{{\displaystyle \frac{100.0}{46.08}}\times 1000}$

C.  $-\frac{100.0\times 4.18\times 10.0}{{\displaystyle \frac{0.230}{46.08}}\times 1000}$

D.  $-\frac{100.0\times 4.18\times 10.0}{{\displaystyle \frac{0.230}{46.08}}}$

What is the enthalpy of combustion, ΔH_c, of ethanol in kJ mol⁻¹?
Maximum temperature of water: 30.0°C
Initial temperature of water: 20.0°C
Mass of water in beaker: 100.0 g
Loss in mass of ethanol: 0.230 g
M_r (ethanol): 46.08
Specific heat capacity of water: 4.18 J g⁻¹ K⁻¹
q = mcΔT

A.  $-\frac{100.0\times 4.18\times (10.0\times 273)}{{\displaystyle \frac{0.230}{46.08}}\times 1000}$

B.  $-\frac{0.0230\times 4.18\times 10.0}{{\displaystyle \frac{100.0}{46.08}}\times 1000}$

C.  $-\frac{100.0\times 4.18\times 10.0}{{\displaystyle \frac{0.230}{46.08}}\times 1000}$

D.  $-\frac{100.0\times 4.18\times 10.0}{{\displaystyle \frac{0.230}{46.08}}}$

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 enthalpy change, in J, when 5 g of water is heated from 10°C to 18°C?

Specific heat capacity of water: 4.18 kJ kg⁻¹ K⁻¹

A.  5 × 4.18 × 8

B.  5 × 10⁻³ × 4.18 × 8

C.  5 × 4.18 × (273 + 8)

D.  5 × 10⁻³ × 4.18 × (273 + 8)

What is the enthalpy change, in J, when 5 g of water is heated from 10°C to 18°C?

Specific heat capacity of water: 4.18 kJ kg⁻¹ K⁻¹

A.  5 × 4.18 × 8

B.  5 × 10⁻³ × 4.18 × 8

C.  5 × 4.18 × (273 + 8)

D.  5 × 10⁻³ × 4.18 × (273 + 8)

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Iron has a relatively small specific heat capacity; the temperature of a 50 g sample rises by 44.4°C when it absorbs 1 kJ of heat energy.

Determine the specific heat capacity of iron, in J g⁻¹K⁻¹. Use section 1 of the data booklet.

Determine the molar enthalpy of combustion of an alkane if 8.75 × 10⁻⁴ moles are burned, raising the temperature of 20.0 g of water by 57.3 °C.

Determine the molar enthalpy of combustion of an alkane if 8.75 × 10⁻⁴ moles are burned, raising the temperature of 20.0 g of water by 57.3 °C.

Determine the molar enthalpy of combustion of an alkane if 8.75 × 10⁻⁴ moles are burned, raising the temperature of 20.0 g of water by 57.3 °C.

The energy from burning 0.250 g of ethanol causes the temperature of 150 cm³ of water to rise by 10.5 °C. What is the enthalpy of combustion of ethanol, in kJ mol^–1?

Specific heat capacity of water: 4.18 J g^–1K^–1.

A.  $\frac{150\times 4.18\times 10.5}{{\displaystyle \frac{0.250}{46.08}}}$

B.  $\frac{150\times 4.18\times 10.5}{{\displaystyle \frac{0.250}{46.08}}\times 1000}$

C.  $\frac{150\times 4.18\times \left(273+10.5\right)}{{\displaystyle \frac{0.250}{46.08}}}$

D.  $\frac{150\times 4.18\times \left(273+10.5\right)}{{\displaystyle \frac{0.250}{46.08}}\times 1000}$

The energy from burning 0.250 g of ethanol causes the temperature of 150 cm³ of water to rise by 10.5 °C. What is the enthalpy of combustion of ethanol, in kJ mol^–1?

Specific heat capacity of water: 4.18 J g^–1K^–1.

A.  $\frac{150\times 4.18\times 10.5}{{\displaystyle \frac{0.250}{46.08}}}$

B.  $\frac{150\times 4.18\times 10.5}{{\displaystyle \frac{0.250}{46.08}}\times 1000}$

C.  $\frac{150\times 4.18\times \left(273+10.5\right)}{{\displaystyle \frac{0.250}{46.08}}}$

D.  $\frac{150\times 4.18\times \left(273+10.5\right)}{{\displaystyle \frac{0.250}{46.08}}\times 1000}$

Discuss two different ways to reduce the environmental impact of energy production from coal.

Discuss two different ways to reduce the environmental impact of energy production from coal.

Discuss two different ways to reduce the environmental impact of energy production from coal.

What happens to the average kinetic energy, KE, of the particles in a gas when the absolute temperature is doubled?

$\mathrm{KE}=\frac{1}{2}\hspace{0.17em}{\mathrm{mv}}^2$

A.  Increases by a factor of 2

B.  Decreases by a factor of 2

C.  Increases by a factor of 4

D.  Decreases by a factor of 4

What happens to the average kinetic energy, KE, of the particles in a gas when the absolute temperature is doubled?

$\mathrm{KE}=\frac{1}{2}\hspace{0.17em}{\mathrm{mv}}^2$

A.  Increases by a factor of 2

B.  Decreases by a factor of 2

C.  Increases by a factor of 4

D.  Decreases by a factor of 4

What happens to the average kinetic energy, KE, of the particles in a gas when the absolute temperature is doubled?

$\mathrm{KE}=\frac{1}{2}\hspace{0.17em}{\mathrm{mv}}^2$

A.  Increases by a factor of 2

B.  Decreases by a factor of 2

C.  Increases by a factor of 4

D.  Decreases by a factor of 4

What happens to the average kinetic energy, KE, of the particles in a gas when the absolute temperature is doubled?

$\mathrm{KE}=\frac{1}{2}\hspace{0.17em}{\mathrm{mv}}^2$

A.  Increases by a factor of 2

B.  Decreases by a factor of 2

C.  Increases by a factor of 4

D.  Decreases by a factor of 4

Which calculation determines the initial rate of this reaction?

A.  $\frac{0.40-0.19}{20-0}$

B.  $\frac{0.40-0.10}{40-0}$

C.  $\frac{0.40-0}{140-0}$

D.  $\frac{0.40-0.20}{10-0}$

Which calculation determines the initial rate of this reaction?

A.  $\frac{0.40-0.19}{20-0}$

B.  $\frac{0.40-0.10}{40-0}$

C.  $\frac{0.40-0}{140-0}$

D.  $\frac{0.40-0.20}{10-0}$

This reaction has an equilibrium constant K_c = 650 at a certain temperature.

NO₂ (g) + SO₂ (g) ⇌ NO + SO₃ (g)

What is the equilibrium constant for the following reaction at the same temperature?

$\frac{1}{2}\mathrm{NO}\hspace{0.17em}\left(\mathrm{g}\right)+\frac{1}{2}{\mathrm{SO}}_3\hspace{0.17em}\left(\mathrm{g}\right)\rightleftharpoons \frac{1}{2}{\mathrm{NO}}_2\hspace{0.17em}\left(\mathrm{g}\right)+\frac{1}{2}{\mathrm{SO}}_2\hspace{0.17em}\left(\mathrm{g}\right)$

A.  $\sqrt{650}$

B.  $\frac{1}{650}$

C.  $\frac{1}{\sqrt{650}}$

D.  $\frac{1}{2}\times 650$

This reaction has an equilibrium constant K_c = 650 at a certain temperature.

NO₂ (g) + SO₂ (g) ⇌ NO + SO₃ (g)

What is the equilibrium constant for the following reaction at the same temperature?

$\frac{1}{2}\mathrm{NO}\hspace{0.17em}\left(\mathrm{g}\right)+\frac{1}{2}{\mathrm{SO}}_3\hspace{0.17em}\left(\mathrm{g}\right)\rightleftharpoons \frac{1}{2}{\mathrm{NO}}_2\hspace{0.17em}\left(\mathrm{g}\right)+\frac{1}{2}{\mathrm{SO}}_2\hspace{0.17em}\left(\mathrm{g}\right)$

A.  $\sqrt{650}$

B.  $\frac{1}{650}$

C.  $\frac{1}{\sqrt{650}}$

D.  $\frac{1}{2}\times 650$

What is the relationship between acid and base dissociation constants in a conjugate acid–base pair?

A.  $K\mathrm{a}\times K\mathrm{b}=K\mathrm{w}$

B.  $\frac{Ka}{Kb}=K\mathrm{w}$

C.  $\mathrm{p}K\mathrm{a}\times \mathrm{p}K\mathrm{b}=\mathrm{p}K\mathrm{w}$

D.  $\frac{pKa}{pKb}=\mathrm{p}K\mathrm{w}$

What is the relationship between acid and base dissociation constants in a conjugate acid–base pair?

A.  $K\mathrm{a}\times K\mathrm{b}=K\mathrm{w}$

B.  $\frac{Ka}{Kb}=K\mathrm{w}$

C.  $\mathrm{p}K\mathrm{a}\times \mathrm{p}K\mathrm{b}=\mathrm{p}K\mathrm{w}$

D.  $\frac{pKa}{pKb}=\mathrm{p}K\mathrm{w}$

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

Which are the correct sequences of increasing bond strengths and bond lengths between two carbon atoms?

Which are the correct sequences of increasing bond strengths and bond lengths between two carbon atoms?

Which condition will cause the given equilibrium to shift to the right?

Ag⁺ (aq) + Cl⁻ (aq) ⇌ AgCl (s)

A.  One half of solid AgCl is removed.

B.  Water is added.

C.  Solid NaCl is added.

D.  The system is subjected to increased pressure.

Which condition will cause the given equilibrium to shift to the right?

Ag⁺ (aq) + Cl⁻ (aq) ⇌ AgCl (s)

A.  One half of solid AgCl is removed.

B.  Water is added.

C.  Solid NaCl is added.

D.  The system is subjected to increased pressure.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

Calculate the pH of the sodium hydroxide solution.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

Calculate the pH of the sodium hydroxide solution.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

Calculate the pH of the sodium hydroxide solution.

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

Nitrogen (IV) oxide exists in equilibrium with dinitrogen tetroxide, N₂O₄(g), which is colourless.

2NO₂ (g) ⇌ N₂O₄ (g)

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

Deduce the overall rate equation.

Deduce the overall rate equation.

Deduce the overall rate equation.