Question 1

Consider the reaction:

What is ΔG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

Accepted Answer

The answer of Consider the reaction:

What is ΔG° for...

Question 2

Consider the following reaction: S₂Cl₂(g) + 2 OCl₂(g) → 2 SOCl₂(g) + Cl₂(g) ΔG°f -32 97.9 -320 0.0 kJ/mol What is Keq for this reaction at 25 °C?

Accepted Answer

The standard Gibbs free energy change (ΔG°) for the reaction can be calculated using the formula ΔG° = ΣΔG°f(products) - ΣΔG°f(reactants). Using the given ΔG°f values, ΔG° = [2(-320) + 0] - [-32 + 2(97.9)] = -648 kJ/mol. The equilibrium constant (Keq) is related to ΔG° by the equation ΔG° = -RTln(Keq). Solving for Keq gives Keq = e^(ΔG°/RT). At 25°C (298 K), R = 8.314 J/mol·K, so Keq = e^(648000/(8.314*298)) = e^324.

Question 3

For the reaction N₂O₃(g) → NO(g) + NO₂(g) ΔG° = -4.78. Calculate Keq at 25°C.

Accepted Answer

The equation relating ΔG° and Keq is:
ΔG° = -RTln(Keq)

We can rearrange this equation to solve for Keq:
Keq = e^(-ΔG°/RT)

Plugging in the given values:
Keq = e^(-(-4.78*10^3 J/mol)/(8.314 J/mol*K * 298 K))

Keq = 1.002

Therefore, the best choice is B.

Question 4

For the reaction I₂(s) + Cl₂(g) → 2 ICl(g) ΔH = 36 kJ and ΔS = 158.8 J/K at 25°C. Calculate the temperature at which Keq is 4.0 × 10³.

Accepted Answer

The correct answer is A.The equilibrium constant Keq is given by the expression:Keq = [ICl]^2 / [I2][Cl2]The change in free energy ΔG is given by the expression:ΔG = -RTlnKeqwhere R is the gas constant (8.314 J/mol·K) and T is the temperature in Kelvin.The change in enthalpy ΔH and the change in entropy ΔS are related to ΔG by the expression:ΔG = ΔH - TΔSAt equilibrium, ΔG = 0, so we can solve for the temperature T:T = ΔH / ΔSSubstituting the given values, we get:T = 36 kJ / 158.8 J/K = 226.7 K = -46.3 °CConverting to Celsius, we get:T = -46.3 °C + 273.15 = 226.85 °CTherefore, the temperature at which Keq is 4.0 × 10^3 is 226.85 °C, which is closest to choice A, 128 °C.

Question 5

Consider the reaction: N₂O₄(g) → 2 NO₂(g) Keq = 0.1134 at 20 °C. ΔH°rxn = 58.03 kJ/mol What is ΔG° for this reaction at 20 °C?

Accepted Answer

ΔG° = -RTlnKeq
where R = 8.314 J/molK, T = 20 + 273 = 293 K, and Keq = 0.1134
ΔG° = -(8.314 J/molK)(293 K)ln(0.1134) /1000 J/kJ
ΔG° = 5.3 kJ/mol (rounded to one decimal place)

Question 6

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol)
What is Keq for this reaction at 377 K?

Accepted Answer

The Van't Hoff equation relates the change in the equilibrium constant (Keq) with temperature: ln(K2/K1) = -ΔH°/R * (1/T2 - 1/T1). Using this equation with the given values, Keq at 377 K is calculated to be approximately 48.5.

Question 7

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is the temperature at which Keq is 1.0 × 10⁴?

Accepted Answer

The answer of For CdO(s) + SO₃(g) → CdSO₄(s) ΔH°...

Question 8

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is ΔG° in kJ/mol at 127 K?

Accepted Answer

The answer of For CdO(s) + SO₃(g) → CdSO₄(s) ΔH°...

Question 9

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is ΔG° in kJ/mol at 300 K?

Accepted Answer

The answer of For CO(g) + H₂(g) → H₂CO(g) ...

Question 10

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K, what is Keq at 200 K if ΔH° = 92.6 kJ/mol?

Accepted Answer

The van't Hoff equation relates the change in equilibrium constant with temperature. Using this equation and given ΔH°, we can calculate the new Keq at 200 K.

Question 11

Consider the endothermic reaction: N₂(g) + O₂(g) → 2 NO(g), ΔH° = 192.5 kJ/mol At 2000 K the equilibrium constant is 5.0 × 10^-4. At 2500 K the value of the equilibrium constant:

Accepted Answer

At higher temperatures, the equilibrium constant for endothermic reactions increases because the reaction shifts in the direction of the products, which increases the concentration of products. Therefore, the equilibrium constant at 2500 K will be greater than 5.0 × 10^-4.

Question 12

Consider the reaction: H₂X(g) → HX(g) + X(g) ΔH°rxn = 18.4 kJ/mol ΔS°rxn = 23.1 J/mol-K What is Keq for this reaction at 525 K?

Accepted Answer

To find Keq, use the equation ΔG° = ΔH° - TΔS°. Convert ΔS° to kJ/mol-K, then calculate ΔG° at 525 K. Use ΔG° = -RTln(Keq) to solve for Keq.

Question 13

What is ΔH° for a reaction that has Kp = 1.456 at 273 K and Kp = 14.2 at 298 K?

Accepted Answer

The change in enthalpy (ΔH°) can be calculated using the van't Hoff equation, which relates the change in the equilibrium constant (Kp) with temperature. The equation is ln(K2/K1) = -ΔH°/R * (1/T2 - 1/T1). Solving this equation with the given values results in ΔH° = 61.6 kJ/mol.

Question 14

For a reaction Keq = 1.2 × 10^-6 at T = 200 K. What is ΔG° for the reaction?

Accepted Answer

The answer of For a reaction Keq = 1.2 ×...

Question 15

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is the temperature at which Keq is 1.0 × 10^-2?

Accepted Answer

The answer of For CO(g) + H₂(g) → H₂CO(g) ...

Question 16

For Cl₂O(g) + 3/2 O₂(g) → 2 ClO₂ ΔH° = 126 kJ/mol, and ΔS° = -74.9 J/mol-deg at 377 °C. What is ΔG° in kJ/mol?

Accepted Answer

The answer of For Cl₂O(g) + 3/2 O₂(g) → 2...

Question 17

Consider the following reaction: 4 NH₃(g) + 7 O₂(g) → 4 NO₂(g) + 6 H₂O (l) ΔG°f -16.7 0.0 51.8 -237.2 kJ/mol What is Keq for this reaction at 25 °C?

Accepted Answer

The equilibrium constant (Keq) can be calculated using the Gibbs free energy change (ΔG°) and the temperature (T) using the equation:Keq = e^(-ΔG°/RT)where R is the ideal gas constant (8.314 J/mol·K).At 25 °C (298 K), the equilibrium constant for the given reaction is:Keq = e^(-(-16.7 kJ/mol)/(8.314 J/mol·K * 298 K)) = e^(464)Therefore, the correct answer is B) e^464.

Question 18

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K. Compute ΔH° for this reaction.

Accepted Answer

The answer of For the reaction PCl₅(g) → PCl₃(g) +...

Question 19

For the reaction SO₂(g) + Cl₂(g) → SO₂Cl₂(g) Keq = 0.377 at 25°C, what is ΔG° for the reaction?

Accepted Answer

The answer of For the reaction SO₂(g) + Cl₂(g) →...

Question 20

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol)
What is Keq for this reaction at 425 K?

Accepted Answer

The answer of Consider the reaction: AB(g) → A(g) +...

Quiz 19: Spontaneous Change: Entropy and Free Energy

Consider the reaction: What is ΔG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

Consider the following reaction: S₂Cl₂(g) + 2 OCl₂(g) → 2 SOCl₂(g) + Cl₂(g) ΔG°f -32 97.9 -320 0.0 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction N₂O₃(g) → NO(g) + NO₂(g) ΔG° = -4.78. Calculate Keq at 25°C.

For the reaction I₂(s) + Cl₂(g) → 2 ICl(g) ΔH = 36 kJ and ΔS = 158.8 J/K at 25°C. Calculate the temperature at which Keq is 4.0 × 10³.

Consider the reaction: N₂O₄(g) → 2 NO₂(g) Keq = 0.1134 at 20 °C. ΔH°rxn = 58.03 kJ/mol What is ΔG° for this reaction at 20 °C?

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol) What is Keq for this reaction at 377 K?

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is the temperature at which Keq is 1.0 × 10⁴?

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is ΔG° in kJ/mol at 127 K?

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is ΔG° in kJ/mol at 300 K?

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K, what is Keq at 200 K if ΔH° = 92.6 kJ/mol?

Consider the endothermic reaction: N₂(g) + O₂(g) → 2 NO(g) , ΔH° = 192.5 kJ/mol At 2000 K the equilibrium constant is 5.0 × 10^-4. At 2500 K the value of the equilibrium constant:

Consider the reaction: H₂X(g) → HX(g) + X(g) ΔH°rxn = 18.4 kJ/mol ΔS°rxn = 23.1 J/mol-K What is Keq for this reaction at 525 K?

What is ΔH° for a reaction that has Kp = 1.456 at 273 K and Kp = 14.2 at 298 K?

For a reaction Keq = 1.2 × 10^-6 at T = 200 K. What is ΔG° for the reaction?

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is the temperature at which Keq is 1.0 × 10^-2?

For Cl₂O(g) + 3/2 O₂(g) → 2 ClO₂ ΔH° = 126 kJ/mol, and ΔS° = -74.9 J/mol-deg at 377 °C. What is ΔG° in kJ/mol?

Consider the following reaction: 4 NH₃(g) + 7 O₂(g) → 4 NO₂(g) + 6 H₂O (l) ΔG°f -16.7 0.0 51.8 -237.2 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K. Compute ΔH° for this reaction.

For the reaction SO₂(g) + Cl₂(g) → SO₂Cl₂(g) Keq = 0.377 at 25°C, what is ΔG° for the reaction?

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol) What is Keq for this reaction at 425 K?

Quiz 19: Spontaneous Change: Entropy and Free Energy

Consider the reaction: What is ΔG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

Consider the following reaction: S2Cl2(g) + 2 OCl2(g) → 2 SOCl2(g) + Cl2(g) ΔG°f -32 97.9 -320 0.0 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction N2O3(g) → NO(g) + NO2(g) ΔG° = -4.78. Calculate Keq at 25°C.

For the reaction I2(s) + Cl2(g) → 2 ICl(g) ΔH = 36 kJ and ΔS = 158.8 J/K at 25°C. Calculate the temperature at which Keq is 4.0 × 103.

Consider the reaction: N2O4(g) → 2 NO2(g) Keq = 0.1134 at 20 °C. ΔH°rxn = 58.03 kJ/mol What is ΔG° for this reaction at 20 °C?

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol) What is Keq for this reaction at 377 K?

For CdO(s) + SO3(g) → CdSO4(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is the temperature at which Keq is 1.0 × 104?

For CdO(s) + SO3(g) → CdSO4(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is ΔG° in kJ/mol at 127 K?

For CO(g) + H2(g) → H2CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is ΔG° in kJ/mol at 300 K?

For the reaction PCl5(g) → PCl3(g) + Cl2(g) at 298 K, Keq = 1.87 × 10-7, ΔS° = 181.92 J/mol K, what is Keq at 200 K if ΔH° = 92.6 kJ/mol?

Consider the endothermic reaction: N2(g) + O2(g) → 2 NO(g) , ΔH° = 192.5 kJ/mol At 2000 K the equilibrium constant is 5.0 × 10-4. At 2500 K the value of the equilibrium constant:

Consider the reaction: H2X(g) → HX(g) + X(g) ΔH°rxn = 18.4 kJ/mol ΔS°rxn = 23.1 J/mol-K What is Keq for this reaction at 525 K?

What is ΔH° for a reaction that has Kp = 1.456 at 273 K and Kp = 14.2 at 298 K?

For a reaction Keq = 1.2 × 10-6 at T = 200 K. What is ΔG° for the reaction?

For CO(g) + H2(g) → H2CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is the temperature at which Keq is 1.0 × 10-2?

For Cl2O(g) + 3/2 O2(g) → 2 ClO2 ΔH° = 126 kJ/mol, and ΔS° = -74.9 J/mol-deg at 377 °C. What is ΔG° in kJ/mol?

Consider the following reaction: 4 NH3(g) + 7 O2(g) → 4 NO2(g) + 6 H2O (l) ΔG°f -16.7 0.0 51.8 -237.2 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction PCl5(g) → PCl3(g) + Cl2(g) at 298 K, Keq = 1.87 × 10-7, ΔS° = 181.92 J/mol K. Compute ΔH° for this reaction.

For the reaction SO2(g) + Cl2(g) → SO2Cl2(g) Keq = 0.377 at 25°C, what is ΔG° for the reaction?

Consider the reaction: AB(g) → A(g) + B(g) (Keq = 0.729 at 20°C ΔH° = 45.9 kJ/mol) What is Keq for this reaction at 425 K?

Consider the following reaction: S₂Cl₂(g) + 2 OCl₂(g) → 2 SOCl₂(g) + Cl₂(g) ΔG°f -32 97.9 -320 0.0 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction N₂O₃(g) → NO(g) + NO₂(g) ΔG° = -4.78. Calculate Keq at 25°C.

For the reaction I₂(s) + Cl₂(g) → 2 ICl(g) ΔH = 36 kJ and ΔS = 158.8 J/K at 25°C. Calculate the temperature at which Keq is 4.0 × 10³.

Consider the reaction: N₂O₄(g) → 2 NO₂(g) Keq = 0.1134 at 20 °C. ΔH°rxn = 58.03 kJ/mol What is ΔG° for this reaction at 20 °C?

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is the temperature at which Keq is 1.0 × 10⁴?

For CdO(s) + SO₃(g) → CdSO₄(s) ΔH° = -279.4 kJ/mol, and ΔS° = -118.4 J/mol-deg. What is ΔG° in kJ/mol at 127 K?

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is ΔG° in kJ/mol at 300 K?

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K, what is Keq at 200 K if ΔH° = 92.6 kJ/mol?

Consider the endothermic reaction: N₂(g) + O₂(g) → 2 NO(g) , ΔH° = 192.5 kJ/mol At 2000 K the equilibrium constant is 5.0 × 10^-4. At 2500 K the value of the equilibrium constant:

Consider the reaction: H₂X(g) → HX(g) + X(g) ΔH°rxn = 18.4 kJ/mol ΔS°rxn = 23.1 J/mol-K What is Keq for this reaction at 525 K?

For a reaction Keq = 1.2 × 10^-6 at T = 200 K. What is ΔG° for the reaction?

For CO(g) + H₂(g) → H₂CO(g) ΔH° = -5.36 kJ/mol, and ΔS° = -109.8 J/mol-deg. What is the temperature at which Keq is 1.0 × 10^-2?

For Cl₂O(g) + 3/2 O₂(g) → 2 ClO₂ ΔH° = 126 kJ/mol, and ΔS° = -74.9 J/mol-deg at 377 °C. What is ΔG° in kJ/mol?

Consider the following reaction: 4 NH₃(g) + 7 O₂(g) → 4 NO₂(g) + 6 H₂O (l) ΔG°f -16.7 0.0 51.8 -237.2 kJ/mol What is Keq for this reaction at 25 °C?

For the reaction PCl₅(g) → PCl₃(g) + Cl₂(g) at 298 K, Keq = 1.87 × 10^-7, ΔS° = 181.92 J/mol K. Compute ΔH° for this reaction.

For the reaction SO₂(g) + Cl₂(g) → SO₂Cl₂(g) Keq = 0.377 at 25°C, what is ΔG° for the reaction?