Question 1

In the reaction $$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$$, what happens if the pressure is increased by reducing the volume of the container?

Accepted Answer

Correct Option: A. Solution: The equilibrium shifts to the left because increasing pressure favors the side with fewer moles of gas.

Question 2

What happens to the equilibrium position when the concentration of a reactant is increased in a dynamic equilibrium system?

Accepted Answer

Correct Option: A. Solution: According to Le Chatelier's principle, increasing the concentration of a reactant will shift the equilibrium to the right to consume the added reactant.

Question 3

Which of the following statements best describes the Arrhenius concept of acids and bases?

Accepted Answer

Correct Option: A. Solution: According to the Arrhenius concept, acids increase the concentration of $H^+$ ions, while bases increase the concentration of $OH^-$ ions in aqueous solutions.

Question 4

In the equilibrium reaction $$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$$, what will be the effect on the equilibrium position if the pressure is increased by adding an inert gas at constant volume?

Accepted Answer

Correct Option: C. Solution: Adding an inert gas at constant volume does not change the partial pressures of the reacting gases, hence the equilibrium position remains unchanged.

Question 5

In the equilibrium reaction $$2NO_2(g) \rightleftharpoons N_2O_4(g)$$, what is the effect of decreasing the temperature?

Accepted Answer

Correct Option: A. Solution: Decreasing the temperature favors the formation of $N_2O_4$ as the reaction is exothermic.

Question 6

Consider the equilibrium reaction: $$N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)$$. If the temperature of the system is increased, what will be the effect on the equilibrium constant $K_c$?

Accepted Answer

Correct Option: B. Solution: The reaction is exothermic ($\Delta H < 0$). According to Le Chatelier's principle, increasing the temperature will shift the equilibrium to the left, favoring the reactants, and thus decrease the equilibrium constant $K_c$.

Question 7

What is the correct relationship between the strength of an acid and its $pK_a$ value?

Accepted Answer

Correct Option: B. Solution: The strength of an acid is inversely related to its $pK_a$ value; a stronger acid has a lower $pK_a$.

Question 8

According to the Bronsted-Lowry concept, which of the following reactions represents an acid donating a proton to a base?

Accepted Answer

Correct Option: B. Solution: In the Bronsted-Lowry concept, an acid is a proton donor and a base is a proton acceptor. In the reaction $HCl + H_2O \rightarrow H_3O^+ + Cl^-$, $HCl$ donates a proton to $H_2O$, forming $H_3O^+$ and $Cl^-$.

Question 9

In the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$, which condition will favor the formation of ammonia according to Le Chatelier's principle?

Accepted Answer

Correct Option: C. Solution: Increasing the pressure will favor the formation of ammonia because the reaction results in a decrease in the number of gas molecules, shifting the equilibrium towards the products.

Question 10

In a closed system at equilibrium, if the concentration of $H_2$ is increased in the reaction $H_2(g) + I_2(g) \rightarrow 2HI(g)$, what will be the effect according to Le Chatelier's principle?

Accepted Answer

Correct Option: A. Solution: According to Le Chatelier's principle, increasing the concentration of $H_2$ will shift the equilibrium to the right to counteract the change, thus favoring the formation of $HI$.

Question 11

Consider a weak base $BOH$ with a $pK_b$ of 4.75. Calculate the $K_b$ for the base.

Accepted Answer

Correct Option: D. Solution: The $K_b$ is calculated using the formula $K_b = 10^{-pK_b}$. Substituting the given value, $K_b = 10^{-4.75} = 3.16 	imes 10^{-5}$.

Question 12

For the endothermic reaction $$2NO_2(g) \rightarrow N_2O_4(g)$$, what is the effect of increasing temperature on the equilibrium constant?

Accepted Answer

Correct Option: B. Solution: For an exothermic reaction, increasing the temperature decreases the equilibrium constant as the equilibrium shifts to the left.

Question 13

For an exothermic reaction, how does the equilibrium constant $K_c$ change with an increase in temperature?

Accepted Answer

Correct Option: B. Solution: For an exothermic reaction, the equilibrium constant $K_c$ decreases as the temperature increases.

Question 14

For the reaction $$2NO_2(g) ightleftharpoons N_2O_4(g)$$ with $\Delta H = -57.2 	ext{ kJ mol}^{-1}$, what will happen if the temperature is decreased?

Accepted Answer

Correct Option: A. Solution: Since the reaction is exothermic, decreasing the temperature will favor the formation of products, shifting the equilibrium to the right to produce more $N_2O_4$.

Question 15

For the reaction $$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$$ at equilibrium, what will happen if the pressure is increased by adding an inert gas at constant volume?

Accepted Answer

Correct Option: C. Solution: Adding an inert gas at constant volume does not change the partial pressures of the reacting gases, so the equilibrium remains unchanged.

Question 16

Consider the equilibrium $$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$$. What will be the effect on the equilibrium position if the pressure is increased by decreasing the volume of the container?

Accepted Answer

Correct Option: B. Solution: Increasing the pressure by decreasing the volume will shift the equilibrium to the left, consuming $CO_2$, as the system tries to decrease the number of moles of gas to counteract the pressure increase.

Question 17

What is the relationship between Gibbs free energy change ($\Delta G$) and the equilibrium constant ($K$) for a reaction at equilibrium?

Accepted Answer

Correct Option: A. Solution: At equilibrium, the Gibbs free energy change $\Delta G = 0$, and the equilibrium constant $K$ is 1, indicating no net change in the system.

Question 18

For the reaction $$2NO_2(g) \rightleftharpoons N_2O_4(g)$$, which of the following statements is true if the temperature is increased?

Accepted Answer

Correct Option: B. Solution: Increasing the temperature favors the endothermic direction. Since the decomposition of $N_2O_4$ into $NO_2$ is endothermic, the equilibrium shifts to the left.

Question 19

In the reaction $$H_2(g) + I_2(g) ightarrow 2HI(g)$$, if the initial concentrations are $[H_2] = 0.10 	ext{ M}$, $[I_2] = 0.20 	ext{ M}$, and $[HI] = 0.40 	ext{ M}$, what is the reaction quotient $Q_c$ and in which direction will the reaction proceed if $K_c = 57.0$ at 700 K?

Accepted Answer

Correct Option: B. Solution: The reaction quotient $Q_c = \frac{(0.40)^2}{(0.10)(0.20)} = 8.0$. Since $Q_c < K_c$, the reaction will proceed to the right to form more $HI$ until equilibrium is reached.

Question 20

In the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$, what will happen if the pressure is increased while keeping the temperature constant?

Accepted Answer

Correct Option: A. Solution: Increasing the pressure favors the side with fewer moles of gas. Since the forward reaction produces fewer moles of gas ($2$ moles of $NH_3$ from $4$ moles of $N_2$ and $H_2$), the equilibrium shifts to the right.

Question 21

According to Le Chatelier's Principle, what will happen if the concentration of $H_2$ is increased in the equilibrium reaction $$H_2(g) + I_2(g) \rightleftharpoons 2HI(g)$$?

Accepted Answer

Correct Option: A. Solution: According to Le Chatelier's Principle, increasing the concentration of $H_2$ will shift the equilibrium to the right to consume the added $H_2$, thus producing more $HI$.

Question 22

In the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$, which of the following changes will shift the equilibrium to the right?

Accepted Answer

Correct Option: A. Solution: Increasing the pressure shifts the equilibrium to the right because it reduces the total number of moles of gas, favoring the formation of $NH_3$.

Question 23

In the equilibrium reaction $$CO(g) + 3H_2(g) \leftrightarrow CH_4(g) + H_2O(g)$$, what will be the effect of increasing the pressure by reducing the volume of the container?

Accepted Answer

Correct Option: A. Solution: Increasing the pressure by reducing the volume favors the side with fewer moles of gas. The forward reaction reduces the number of moles from 4 to 2, thus shifting the equilibrium to the right.

Question 24

For the equilibrium reaction $$2NO_2(g) \rightleftharpoons N_2O_4(g)$$, which of the following statements is true when the temperature is increased?

Accepted Answer

Correct Option: B. Solution: The equilibrium constant $K_c$ decreases because the reaction is exothermic, and increasing temperature favors the endothermic reverse reaction.

Question 25

In the context of the Haber process for ammonia synthesis, how does an increase in temperature affect the equilibrium position?

Accepted Answer

Correct Option: B. Solution: The Haber process is exothermic, so increasing the temperature shifts the equilibrium to the left, reducing ammonia production according to Le Chatelier's principle.

Question 26

Considering the reaction $2NO_2(g) \rightarrow N_2O_4(g)$, which is exothermic, how will an increase in temperature affect the equilibrium constant $K_c$?

Accepted Answer

Correct Option: B. Solution: For exothermic reactions, increasing the temperature decreases the equilibrium constant $K_c$ as the equilibrium shifts to the left, favoring the reactants.

Question 27

What is the effect of temperature on the equilibrium constant $K_c$ for an exothermic reaction?

Accepted Answer

Correct Option: B. Solution: For an exothermic reaction, the equilibrium constant $K_c$ decreases as the temperature increases.

Question 28

Which of the following correctly represents the equilibrium constant expression for the reaction $$H_2(g) + I_2(g) \rightleftharpoons 2HI(g)$$?

Accepted Answer

Correct Option: A. Solution: The equilibrium constant expression for the reaction is $K_c = \frac{[HI]^2}{[H_2][I_2]}$, based on the stoichiometric coefficients.

Question 29

In a closed system at equilibrium, what happens to the equilibrium position when the concentration of a reactant is increased?

Accepted Answer

Correct Option: A. Solution: According to Le Chatelier's principle, increasing the concentration of a reactant will shift the equilibrium to the right, favoring the formation of products.

Question 30

Consider a weak acid $HA$ with an ionization constant $K_a$. If the initial concentration of $HA$ is $0.1 \, M$ and the degree of ionization is $0.01$, what is the value of $K_a$?

Accepted Answer

Correct Option: A. Solution: The ionization constant $K_a$ is given by $K_a = c \alpha^2$, where $c$ is the initial concentration and $\alpha$ is the degree of ionization. Substituting the given values: $K_a = 0.1 	imes (0.01)^2 = 1.0 	imes 10^{-4}$.

Question 31

In a heterogeneous equilibrium involving the thermal decomposition of calcium carbonate, which species is included in the equilibrium constant expression?

Accepted Answer

Correct Option: C. Solution: In heterogeneous equilibria, only the concentrations of gases and aqueous solutions are included in the equilibrium constant expression. Thus, only $CO_2(g)$ is included.

Question 32

For the reaction $$N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)$$, if the equilibrium constant $K_c$ is known to decrease with an increase in temperature, what can be inferred about the reaction?

Accepted Answer

Correct Option: B. Solution: The equilibrium constant $K_c$ decreases with an increase in temperature for exothermic reactions. This indicates that the reaction releases heat.

Question 33

For the reaction $$2NO_2(g) \rightleftharpoons N_2O_4(g)$$, which is exothermic, what will be the effect on the equilibrium constant $K_c$ if the temperature is decreased?

Accepted Answer

Correct Option: A. Solution: For an exothermic reaction, decreasing the temperature increases the equilibrium constant $K_c$, as the reaction shifts to the right, favoring the formation of $N_2O_4$.

Question 34

For the reaction $$N_2(g) + 3H_2(g) ightarrow 2NH_3(g)$$, if the equilibrium constant $K_c$ at a certain temperature is known to be $6.8 	imes 10^5$, what can be inferred about the concentrations of reactants and products at equilibrium?

Accepted Answer

Correct Option: A. Solution: A high equilibrium constant $K_c$ indicates that the products ($NH_3$) are favored at equilibrium, meaning their concentration is much higher than the reactants ($N_2$ and $H_2$).

Question 35

Which of the following statements is true regarding the effect of concentration changes on chemical equilibrium according to Le Chatelier's principle?

Accepted Answer

Correct Option: B. Solution: According to Le Chatelier's principle, removing a product will shift the equilibrium to the right to produce more product.

Question 36

In the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$, what effect does increasing the pressure have on the equilibrium position?

Accepted Answer

Correct Option: A. Solution: Increasing the pressure shifts the equilibrium towards the side with fewer moles of gas, which is the formation of ammonia in this case.

Question 37

According to Le Chatelier's principle, what will be the effect on the equilibrium position of the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$ if the pressure is increased by decreasing the volume of the container?

Accepted Answer

Correct Option: A. Solution: According to Le Chatelier's principle, increasing the pressure by decreasing the volume shifts the equilibrium towards the side with fewer moles of gas. In this case, the equilibrium shifts to the right, favoring the formation of $NH_3$ which has fewer moles of gas.

Question 38

Consider the reaction $$H_2(g) + I_2(g) \rightleftharpoons 2HI(g)$$. If the concentration of $HI$ is increased, what will be the effect on the equilibrium position?

Accepted Answer

Correct Option: B. Solution: According to Le Chatelier's principle, increasing the concentration of $HI$ will shift the equilibrium to the left to consume the added product.

Question 39

What is the relationship between the pH and pOH of a solution at 25°C?

Accepted Answer

Correct Option: A. Solution: At 25°C, the ionic product of water $K_w$ is $1.0 	imes 10^{-14}$, leading to the relationship $pH + pOH = 14$.

Question 40

A weak base $BOH$ has an ionization constant $K_b$. If the initial concentration of $BOH$ is $0.05 \, M$ and the degree of ionization is $0.02$, what is the value of $K_b$?

Accepted Answer

Correct Option: B. Solution: The ionization constant $K_b$ is given by $K_b = c \alpha^2$, where $c$ is the initial concentration and $\alpha$ is the degree of ionization. Substituting the given values: $K_b = 0.05 	imes (0.02)^2 = 2.0 	imes 10^{-6}$.

Question 41

In the reaction $$C(s) + CO_2(g) \rightarrow 2CO(g)$$, what will be the effect of adding an inert gas at constant volume?

Accepted Answer

Correct Option: C. Solution: Adding an inert gas at constant volume does not change the partial pressures of the reacting gases, so the equilibrium position remains unchanged.

Question 42

Consider the reaction $$2NO_2(g) \leftrightarrow N_2O_4(g)$$ with $\Delta H = -57.2 	ext{ kJ mol}^{-1}$. If the temperature is increased, what will be the effect on the equilibrium position?

Accepted Answer

Correct Option: B. Solution: Increasing the temperature of an exothermic reaction shifts the equilibrium to the left, favoring the reactants ($NO_2$) as per Le Chatelier's principle.

Question 43

In which direction will the equilibrium shift if the concentration of $H_2$ is increased in the reaction $H_2(g) + I_2(g) \rightleftharpoons 2HI(g)$?

Accepted Answer

Correct Option: B. Solution: According to Le Chatelier's principle, increasing the concentration of $H_2$ will shift the equilibrium to the right to consume the added $H_2$ and form more $HI$.

Question 44

Which of the following statements is true about the dynamic nature of chemical equilibrium?

Accepted Answer

Correct Option: B. Solution: At dynamic equilibrium, the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products.

Question 45

Given the reaction $$HA ightleftharpoons H^+ + A^-$$ with an ionization constant $K_a = 1.8 	imes 10^{-5}$, calculate the $pK_a$ of the acid.

Accepted Answer

Correct Option: A. Solution: The $pK_a$ is calculated using the formula $pK_a = -\log K_a$. Substituting the given value, $pK_a = -\log(1.8 	imes 10^{-5}) = 4.74$.

Question 46

Consider the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$ which is exothermic. According to Le Chatelier's principle, what will be the effect on the equilibrium position if the temperature is increased?

Accepted Answer

Correct Option: B. Solution: Increasing the temperature of an exothermic reaction shifts the equilibrium to the left, favoring the decomposition of $NH_3$ to $N_2$ and $H_2$.

Question 47

For the reaction $$N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)$$, which of the following statements is true regarding the effect of temperature on the equilibrium constant $K_c$?

Accepted Answer

Correct Option: B. Solution: For exothermic reactions like the synthesis of ammonia, the equilibrium constant $K_c$ decreases as the temperature increases.

Question 48

For the reaction $$2NO_2(g) \rightarrow N_2O_4(g)$$, which of the following changes will shift the equilibrium to the right?

Accepted Answer

Correct Option: B. Solution: The reaction $$2NO_2(g) \rightarrow N_2O_4(g)$$ is exothermic. According to Le Chatelier's principle, decreasing the temperature will shift the equilibrium to the right, favoring the formation of $N_2O_4$.

Question 49

Given the reaction $$NH_3 + H_2O \rightleftharpoons NH_4^+ + OH^-$$, if the $pK_b$ of $NH_3$ is 4.75, what can be inferred about the strength of $NH_3$ as a base?

Accepted Answer

Correct Option: B. Solution: A higher $pK_b$ value indicates a weaker base. Since $NH_3$ has a $pK_b$ of 4.75, it is a weak base.

Question 50

Which of the following statements is true regarding the Lewis concept of acids and bases?

Accepted Answer

Correct Option: C. Solution: According to the Lewis concept, a Lewis acid is a substance that can accept a pair of electrons, while a Lewis base is a substance that can donate a pair of electrons.

Question 51

The equilibrium constant $K_c$ for a reaction changes with the initial concentrations of reactants and products.

Accepted Answer

Answer: False. Solution: The equilibrium constant $K_c$ is independent of the initial concentrations of reactants and products; it only depends on temperature.

Question 52

According to Le Chatelier's principle, increasing the concentration of a reactant in an equilibrium system will shift the equilibrium position to the left.

Accepted Answer

Answer: False. Solution: According to Le Chatelier's principle, increasing the concentration of a reactant will shift the equilibrium position to the right, favoring the formation of products.

Question 53

The equilibrium constant $K_c$ is independent of the initial concentrations of reactants and products.

Accepted Answer

Answer: True. Solution: The equilibrium constant $K_c$ is a characteristic of the reaction at a given temperature and does not depend on the initial concentrations of reactants and products.

Question 54

In a dynamic chemical equilibrium, the concentrations of reactants and products remain constant because the rates of the forward and reverse reactions are equal.

Accepted Answer

Answer: True. Solution: Dynamic equilibrium is characterized by the rates of the forward and reverse reactions being equal, resulting in constant concentrations of reactants and products.

Question 55

The reaction quotient $Q_c$ is used to predict the direction of a reaction by comparing it with the equilibrium constant $K_c$.

Accepted Answer

Answer: True. Solution: The reaction quotient $Q_c$ is calculated similarly to the equilibrium constant $K_c$, but with concentrations that are not necessarily at equilibrium. By comparing $Q_c$ with $K_c$, we can predict whether the reaction will proceed in the forward or reverse direction to reach equilibrium.

Question 56

The equilibrium constant $K_w$ for the ionization of water is dependent on temperature.

Accepted Answer

Answer: True. Solution: The equilibrium constant $K_w$ is indeed dependent on temperature, as changes in temperature can affect the ionization equilibrium of water.

Question 57

In a dynamic chemical equilibrium, the concentrations of reactants and products remain constant because the rates of the forward and reverse reactions are equal.

Accepted Answer

Answer: True. Solution: Dynamic equilibrium is characterized by equal rates of forward and reverse reactions, leading to constant concentrations of reactants and products.

Question 58

According to Le Chatelier's Principle, if the concentration of a reactant in a chemical equilibrium is increased, the system will adjust to consume some of the added reactant.

Accepted Answer

Answer: True. Solution: Le Chatelier's Principle states that if a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the system will adjust to counteract the effect of the change. Increasing the concentration of a reactant will shift the equilibrium to the right, consuming some of the added reactant.

Question 59

According to the Bronsted-Lowry concept, an acid is a substance that donates a proton.

Accepted Answer

Answer: True. Solution: The Bronsted-Lowry concept defines an acid as a proton donor.

Question 60

According to Le Chatelier's principle, increasing the pressure on a gaseous reaction where the number of moles of gaseous reactants is greater than the number of moles of gaseous products will shift the equilibrium towards the products.

Accepted Answer

Answer: True. Solution: Le Chatelier's principle states that if a system at equilibrium is subjected to a change in pressure, the equilibrium will shift in the direction that reduces the pressure. For a gaseous reaction, increasing the pressure will favor the direction with fewer moles of gas. Therefore, if the number of moles of gaseous reactants is greater than that of the products, the equilibrium will shift towards the products.

Question 61

In an exothermic reaction, the equilibrium constant $K$ decreases with an increase in temperature.

Accepted Answer

Answer: True. Solution: According to the principles of chemical equilibrium, for an exothermic reaction (where $\Delta H$ is negative), the equilibrium constant $K$ decreases as the temperature increases. This is because increasing the temperature shifts the equilibrium towards the reactants to absorb the excess heat, according to Le Chatelier's principle.

Question 62

In heterogeneous equilibria, the equilibrium constant expressions exclude the concentrations of pure solids and liquids.

Accepted Answer

Answer: True. Solution: In heterogeneous equilibria, the concentrations of pure solids and liquids are constant and do not appear in the equilibrium constant expression.

Question 63

For an exothermic reaction, the equilibrium constant decreases as the temperature increases.

Accepted Answer

Answer: True. Solution: According to the principle of temperature dependence of equilibrium, the equilibrium constant for an exothermic reaction decreases with an increase in temperature.

Question 64

In heterogeneous equilibria, the equilibrium constant expressions exclude pure solids and liquids.

Accepted Answer

Answer: True. Solution: In heterogeneous equilibria, the equilibrium constant expressions do not include the concentrations of pure solids and liquids because their concentrations are constant.

Equilibrium

Learning Objectives

Learning Objectives

Revision Notes & Summary

Chapter Notes

Dynamic Chemical Equilibrium

Equilibrium Constant Expressions

Le Chatelier's Principle

Temperature Dependence of Equilibrium

Heterogeneous Equilibria

Reaction Quotient (Qc)

Gibbs Free Energy and Equilibrium

Equilibrium in Physical Processes

Applications of Equilibrium Constant

Acids and Bases: Arrhenius, Bronsted-Lowry and Lewis Concepts

Ionisation Constants of Weak Acids and Weak Bases

Ionisation of Water, Kw, pH and pOH

pKa, pKb and Strength of Acids/Bases

Buffer Solutions

Exam Tips & Common Mistakes

Common Mistakes & Exam Tips

Dynamic Chemical Equilibrium

Equilibrium Constant Expressions

Le Chatelier's Principle

Temperature Dependence of Equilibrium

Heterogeneous Equilibria

Reaction Quotient (Qc)

Gibbs Free Energy and Equilibrium

Equilibrium in Physical Processes

Applications of Equilibrium Constant

Acids and Bases: Arrhenius, Bronsted-Lowry, and Lewis Concepts

Ionisation Constants of Weak Acids and Weak Bases

Ionisation of Water, Kw, pH and pOH

pKa, pKb and Strength of Acids/Bases

Buffer Solutions

AI Learning Assistant

Practice Test – MCQs, True/False

Practice, Analyze & Improve 🚀

Multiple Choice Questions

Q1.In the reaction CaCO3(s)⇌CaO(s)+CO2(g)CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)CaCO3​(s)⇌CaO(s)+CO2​(g), what happens if the pressure is increased by reducing the volume of the container?

Correct Answer: A

Q2.What happens to the equilibrium position when the concentration of a reactant is increased in a dynamic equilibrium system?

Correct Answer: A

Q3.Which of the following statements best describes the Arrhenius concept of acids and bases?

Correct Answer: A

Q4.In the equilibrium reaction CaCO3(s)⇌CaO(s)+CO2(g)CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)CaCO3​(s)⇌CaO(s)+CO2​(g), what will be the effect on the equilibrium position if the pressure is increased by adding an inert gas at constant volume?

Correct Answer: C

Q5.In the equilibrium reaction 2NO2(g)⇌N2O4(g)2NO_2(g) \rightleftharpoons N_2O_4(g)2NO2​(g)⇌N2​O4​(g), what is the effect of decreasing the temperature?

Correct Answer: A

Q6.Consider the equilibrium reaction: N2(g)+3H2(g)⇌2NH3(g)N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g)N2​(g)+3H2​(g)⇌2NH3​(g). If the temperature of the system is increased, what will be the effect on the equilibrium constant KcK_cKc​?

Correct Answer: B

Q7.What is the correct relationship between the strength of an acid and its pKapK_apKa​ value?

Correct Answer: B

Q8.According to the Bronsted-Lowry concept, which of the following reactions represents an acid donating a proton to a base?

Correct Answer: B

Q9.In the reaction N2(g)+3H2(g)→2NH3(g)N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)N2​(g)+3H2​(g)→2NH3​(g), which condition will favor the formation of ammonia according to Le Chatelier's principle?

Correct Answer: C

Q10.In a closed system at equilibrium, if the concentration of H2H_2H2​ is increased in the reaction H2(g)+I2(g)→2HI(g)H_2(g) + I_2(g) \rightarrow 2HI(g)H2​(g)+I2​(g)→2HI(g), what will be the effect according to Le Chatelier's principle?

Correct Answer: A

Q11.Consider a weak base BOHBOHBOH with a pKbpK_bpKb​ of 4.75. Calculate the KbK_bKb​ for the base.

Correct Answer: D

Q12.For the endothermic reaction 2NO2(g)→N2O4(g)2NO_2(g) \rightarrow N_2O_4(g)2NO2​(g)→N2​O4​(g), what is the effect of increasing temperature on the equilibrium constant?

Correct Answer: B

Q13.For an exothermic reaction, how does the equilibrium constant KcK_cKc​ change with an increase in temperature?

Correct Answer: B

Q14.For the reaction 2NO2(g)⇌N2O4(g)2NO_2(g) \rightleftharpoons N_2O_4(g)2NO2​(g)⇌N2​O4​(g) with ΔH=−57.2 kJ mol−1\Delta H = -57.2 \text{ kJ mol}^{-1}ΔH=−57.2 kJ mol−1, what will happen if the temperature is decreased?

Correct Answer: A

Q15.For the reaction CaCO3(s)⇌CaO(s)+CO2(g)CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)CaCO3​(s)⇌CaO(s)+CO2​(g) at equilibrium, what will happen if the pressure is increased by adding an inert gas at constant volume?

Correct Answer: C

Q16.Consider the equilibrium CaCO3(s)⇌CaO(s)+CO2(g)CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)CaCO3​(s)⇌CaO(s)+CO2​(g). What will be the effect on the equilibrium position if the pressure is increased by decreasing the volume of the container?

Correct Answer: B

Q17.What is the relationship between Gibbs free energy change (ΔG\Delta GΔG) and the equilibrium constant (KKK) for a reaction at equilibrium?

Correct Answer: A

Q18.For the reaction 2NO2(g)⇌N2O4(g)2NO_2(g) \rightleftharpoons N_2O_4(g)2NO2​(g)⇌N2​O4​(g), which of the following statements is true if the temperature is increased?

Correct Answer: B

Correct Answer: B

Q20.In the reaction N2(g)+3H2(g)→2NH3(g)N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)N2​(g)+3H2​(g)→2NH3​(g), what will happen if the pressure is increased while keeping the temperature constant?

Correct Answer: A

Q21.According to Le Chatelier's Principle, what will happen if the concentration of H2H_2H2​ is increased in the equilibrium reaction H2(g)+I2(g)⇌2HI(g)H_2(g) + I_2(g) \rightleftharpoons 2HI(g)H2​(g)+I2​(g)⇌2HI(g)?

Correct Answer: A