Q: Arrange the following acids in order of increasing strength: HF(aq), HBr(aq), HI(aq) Which is the strongest acid?

HF < HBr < HI; HI is the strongest

Q: Given the following reaction: $\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$ At 298 K, $\Delta G^\circ = -33.2$ kJ/mol. Is this reaction spontaneous under standard conditions?

Yes, because $\Delta G^\circ$ is negative

Q: Which of the following statements about entropy ($S$) is correct?

Entropy is a measure of the disorder or randomness of a system

Q: Consider the reaction $\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$. If the reaction quotient $Q$ is less than the equilibrium constant $K$, in which direction will the reaction proceed?

The reaction will proceed in the forward direction

Q: Given the reaction $\mathrm{2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)}$, which of the following will shift the equilibrium to the right?

Increasing the concentration of $\mathrm{SO_2}$

Q: Which of the following is the correct mathematical expression for the reaction quotient $Q$ for the reaction $\mathrm{2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)}$?

$Q = \dfrac{[SO_3]^2}{[SO_2]^2[O_2]}$

Q: A decrease in volume for the reaction $\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$ will have what effect on the equilibrium?

Shift equilibrium to the right (toward $\mathrm{NH_3}$)

Q: Which of the following is true about the relationship between $\Delta G$ and $\Delta G^\circ$?

$\Delta G = \Delta G^\circ + RT \ln Q$

Q: Which of the following is the correct expression for the equilibrium constant $K_p$ for the reaction $\mathrm{N_2O_4(g) \rightarrow 2NO_2(g)}$?

$K_p = \dfrac{(P_{NO_2})^2}{P_{N_2O_4}}$

Question 1

Which of the following processes is spontaneous under standard conditions? 
A. A raindrop falling to the ground 
B. Iron rusting in a moist atmosphere 
C. Water freezing at 25°C 
D. Dissolving NaCl in water at 25°C

Accepted Answer

A raindrop falling to the ground

Question 2

Arrange the following acids in order of increasing strength: 
HF(aq), HBr(aq), HI(aq) 
Which is the strongest acid?

Accepted Answer

HF < HBr < HI; HI is the strongest

Question 3

Given the following reaction: 
$\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$ 
At 298 K, $\Delta G^\circ = -33.2$ kJ/mol. Is this reaction spontaneous under standard conditions?

Accepted Answer

Yes, because $\Delta G^\circ$ is negative

Question 4

Which equation correctly relates the equilibrium constant $K$ to the standard Gibbs free energy change $\Delta G^\circ$ at temperature $T$?

Accepted Answer

$\Delta G^\circ = -RT \ln K$

Question 5

For the reaction $\mathrm{CO_2(g) + C(s) ightarrow 2CO(g)}$ at 298 K, the equilibrium constant $K = 1.64 	imes 10^{-6}$. What is the value of $\Delta G^\circ$ for this reaction at 298 K?

Accepted Answer

$\Delta G^\circ = 32.8$ kJ/mol

Question 6

Which of the following statements about entropy ($S$) is correct?

Accepted Answer

Entropy is a measure of the disorder or randomness of a system

Question 7

Consider the reaction $\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$. If the reaction quotient $Q$ is less than the equilibrium constant $K$, in which direction will the reaction proceed?

Accepted Answer

The reaction will proceed in the forward direction

Question 8

Which of the following changes will increase the equilibrium constant $K$ for an endothermic reaction?

Accepted Answer

Increasing the temperature

Question 9

Given the reaction $\mathrm{2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)}$, which of the following will shift the equilibrium to the right?

Accepted Answer

Increasing the concentration of $\mathrm{SO_2}$

Question 10

Which of the following is the correct mathematical expression for the reaction quotient $Q$ for the reaction $\mathrm{2SO_2(g) + O_2(g) \rightarrow 2SO_3(g)}$?

Accepted Answer

$Q = \dfrac{[SO_3]^2}{[SO_2]^2[O_2]}$

Question 11

A decrease in volume for the reaction $\mathrm{N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)}$ will have what effect on the equilibrium?

Accepted Answer

Shift equilibrium to the right (toward $\mathrm{NH_3}$)

Question 12

Which of the following is true about the relationship between $\Delta G$ and $\Delta G^\circ$?

Accepted Answer

$\Delta G = \Delta G^\circ + RT \ln Q$

Question 13

For the reaction $\mathrm{2HgO(s) \rightarrow 2Hg(l) + O_2(g)}$, $\Delta H = +182$ kJ. How will an increase in temperature affect the equilibrium?

Accepted Answer

Shift equilibrium to the right

Question 14

Which of the following is the correct expression for the equilibrium constant $K_p$ for the reaction $\mathrm{N_2O_4(g) \rightarrow 2NO_2(g)}$?

Accepted Answer

$K_p = \dfrac{(P_{NO_2})^2}{P_{N_2O_4}}$

Question 15

If $\Delta G^\circ$ for a reaction is positive, what can be said about the equilibrium constant $K$?

Accepted Answer

$K < 1$

Question 16

Which of the following is a correct statement about the effect of a catalyst on a chemical equilibrium?

Accepted Answer

A catalyst does not affect the position of equilibrium

Question 17

For the reaction $\mathrm{CaCO_3(s) \rightarrow CaO(s) + CO_2(g)}$, which of the following will increase the amount of $\mathrm{CO_2}$ produced at equilibrium?

Accepted Answer

Decreasing the pressure

Question 18

Which of the following is the correct formula for calculating $\Delta G^\circ$ from $\Delta H^\circ$ and $\Delta S^\circ$?

Accepted Answer

$\Delta G^\circ = \Delta H^\circ - T \Delta S^\circ$

Question 19

A reaction has $\Delta H^\circ = -100$ kJ and $\Delta S^\circ = -200$ J/K. At what temperature will the reaction become non-spontaneous?

Accepted Answer

$T > 500$ K

Chemical Equilibrium and Thermodynamics: Study Notes and Key Equations

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