Question 1

Which of the following reactions will not shift toward the reactants products when the pressure of the system is altered by changing the volume?

Accepted Answer

The answer of Which of the following reactions will not...

Question 2

In a simple equilibrium A + B  C, will there be any stress to the system if both B and C are added to the equilibrium system simultaneously and in the same amount?

Accepted Answer

The answer of In a simple equilibrium A + B...

Question 3

Cylinders of NO gas may contain small quantities of oxygen as an impurity, leading to the formation of NO₂ in equilibrium with the NO and the oxygen. Is this contamination by NO₂ dependent on the pressure in the tank?

Accepted Answer

The formation of NO₂ (N2O, nitrous oxide) from NO and O2 is governed by Le Chatelier's principle, which states that increasing the pressure will shift the equilibrium towards the side with fewer gas molecules, in this case, forming more N2O.

Question 4

Which of the following occurs when products are removed from a chemical reaction in solution or the gas phase at equilibrium?

Accepted Answer

When products are removed from a reaction at equilibrium, the reaction quotient Q decreases, causing the equilibrium to shift to the right to produce more products to re-establish equilibrium.

Question 5

If the temperature of an endothermic reaction at equilibrium could be increased instantaneously, what would be the instantaneous effect on Q and K before equilibrium was again achieved?

Accepted Answer

For an endothermic reaction, increasing the temperature shifts the equilibrium to favor the products, which increases the value of the equilibrium constant, K. The reaction quotient, Q, remains unchanged immediately after the temperature change because it reflects the ratio of concentrations at that moment, which have not yet adjusted to the new temperature.

Question 6

Given the reaction below, which of the following would cause an increase in the concentration of products? 4NH₃(g) F+ 3O₂(g) 2N₂(g) + 6H₂O(g) I. addition of water II. removal of ammonia III. decrease of the volume of the container IV. addition of oxygen

Accepted Answer

The answer of Given the reaction below, which of the...

Question 7

Given the reaction below, which of the following would cause an increase in the concentration of reactants? 2HF(g) F₂(g) + H₂(g) H^°= -12.0 kJ/mol I. removal of hydrogen II. addition of HF III. increasing the temperature of the reaction IV. an increase in the volume of the container

Accepted Answer

The answer of Given the reaction below, which of the...

Question 8

Carbon dioxide and argon, which is a noble or inert gas, are placed in a vessel and heated. Equilibrium is reached at some particular temperature. Carbon dioxide dissociates by the following reaction. 2CO₂(g) 2CO(g) + O₂(g) What is the result of increasing the pressure by adding more argon? I. The equilibrium shifts to produce more carbon dioxide and reduce the pressure. II. The equilibrium shifts to remove carbon dioxide and reduce the pressure. III. The equilibrium does not change because argon is not involved in the reaction. IV. The equilibrium does not change because the concentrations are not affected.

Accepted Answer

The answer of Carbon dioxide and argon, which is a...

Question 9

What happens to the equilibrium between NO₂(g) and N₂O₄(g) in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?

Accepted Answer

The answer of What happens to the equilibrium between NO₂(g)...

Question 10

In the Reaction, Initial, Change, Equilibrium (RICE) table started for calculating equilibrium concentrations of the reaction shown, the terms in the "change" row are ________

Accepted Answer

The change row in the RICE table indicates the change in concentration of the reactants and products from the initial state to the equilibrium state. The change in concentration for the reactant (F1F1F1S1) is -F1F1F10x because it is being consumed, and the change in concentration for the product (F1F1F1S1F1F1F10) is +F1F1F10x because it is being produced. The other two species in the reaction (F1F1F1S1− and F1F1F1S1+) are not involved in the reaction itself and therefore do not change. Therefore, the correct answer is C.

Question 11

Solid mercury(II) oxide decomposes when heated to produce liquid mercury and oxygen. 2HgO(s) 2Hg(l) + O₂(g) An amount of mercury(II) oxide is placed in a vessel at a particular temperature and allowed to reach equilibrium. How could the amount of liquid mercury in the vessel be increased? I. adding more mercury(II) oxide II. removing some oxygen III. increasing the volume of the vessel

Accepted Answer

The answer of Solid mercury(II) oxide decomposes when heated to...

Question 12

Which of the following is true regarding the effect of a catalyst on chemical equilibrium?

Accepted Answer

A catalyst increases the rate of both the forward and reverse reactions, but it does not affect the position of equilibrium. Therefore, the quantity of products remains the same.

Question 13

For a chemical reaction at equilibrium, which of the following will change the value of the equilibrium constant K?
I.changing the temperature
II.changing the total concentration of reactants and products
III.changing the reaction coefficients

Accepted Answer

The answer of For a chemical reaction at equilibrium, which...

Question 14

Addition of reactants to a chemical reaction in solution or gas phase at equilibrium results in ________

Accepted Answer

The addition of reactants to a chemical reaction at equilibrium does not change the equilibrium constant (K) but shifts the equilibrium towards the products to re-establish equilibrium, according to Le Chatelier's principle.

Question 15

Identify whether or not perturbations A-D will affect the equilibrium concentrations of reactants and products in a gas-phase endothermic chemical reaction that involves one or more gases. If all have an effect on the equilibrium concentrations, select response E. Otherwise, identify the one that does not affect the equilibrium concentrations.

Accepted Answer

Increasing pressure by adding an inert gas to a reaction in the gas phase does not affect the equilibrium concentrations because an inert gas does not participate in the reaction. The partial pressures of the reactants and products remain the same, and the equilibrium position does not change. 
Choices A, B, and C all affect the equilibrium concentrations because they change the reaction conditions and shift the equilibrium towards the side with fewer moles of gas (Le Chatelier's principle). Therefore, E is also a valid choice as all of the perturbations have an effect on the equilibrium concentrations.

Question 16

Increasing the temperature of an exothermic reaction results in ________

Accepted Answer

According to Le Chatelier's Principle, increasing the temperature of an exothermic reaction will shift the equilibrium towards the reactants to partially offset the increase in temperature. Therefore, there would be more reactants and fewer products.

Question 17

Which of the following occurs when reactants are added to a chemical reaction in solution or the gas phase at equilibrium?

Accepted Answer

When reactants are added, Q decreases because the concentration of reactants increases, causing the equilibrium to shift towards the products to re-establish equilibrium.

Question 18

Addition of products to a chemical reaction in solution or gas phase at equilibrium results in ________

Accepted Answer

Adding products to a reaction at equilibrium does not change the equilibrium constant (K), but it shifts the equilibrium to the left to produce more reactants, according to Le Chatelier's principle.

Question 19

How would an increase in temperature affect the following equilibrium? N₂(g) + 3H₂(g) 2NH₃(g) H^° = -92.0 kJ/mol

Accepted Answer

According to Le Chatelier's principle, an increase in temperature would favor the endothermic reaction (i.e. the reaction with the positive ∆H value). In this case, that means more reactants would form. As a result, the equilibrium constant, K, would decrease. Therefore, the correct answer is E.

Question 20

How would an increase in temperature affect the following equilibrium? H₂O(l ) H₂(g) + O₂(g) HS1U1P1$\circ$S1S1P0 = 482.0 kJ/mol

Accepted Answer

The answer of How would an increase in temperature affect...

Quiz 14: Chemical Equilibrium: How Much Product Does a Reaction Really Make

Which of the following reactions will not shift toward the reactants products when the pressure of the system is altered by changing the volume?

In a simple equilibrium A + B C, will there be any stress to the system if both B and C are added to the equilibrium system simultaneously and in the same amount?

Cylinders of NO gas may contain small quantities of oxygen as an impurity, leading to the formation of NO2 in equilibrium with the NO and the oxygen. Is this contamination by NO2 dependent on the pressure in the tank?

Which of the following occurs when products are removed from a chemical reaction in solution or the gas phase at equilibrium?

If the temperature of an endothermic reaction at equilibrium could be increased instantaneously, what would be the instantaneous effect on Q and K before equilibrium was again achieved?

Given the reaction below, which of the following would cause an increase in the concentration of products? 4NH3(g) F+ 3O2(g) 2N2(g) + 6H2O(g) I. addition of water II. removal of ammonia III. decrease of the volume of the container IV. addition of oxygen

Given the reaction below, which of the following would cause an increase in the concentration of reactants? 2HF(g) F2(g) + H2(g) H°= -12.0 kJ/mol I. removal of hydrogen II. addition of HF III. increasing the temperature of the reaction IV. an increase in the volume of the container

What happens to the equilibrium between NO2(g) and N2O4(g) in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?