Directions: Answer each of the following questions.

Le Châtelier’s Principle

Predict the direction of the equilibrium shift for each of the following processes:

1. H2(g) + Cl2(g) ⇄ 2 HCl(g)

What direction will the equilibrium shift when the partial pressure of hydrogen is increased?

2. 3 H2(g) + N2(g) ⇄ 2 NH3(g)

Given that this reaction is exothermic, what direction will the equilibrium shift when the temperature of the reaction is decreased?

3. 2 NO2(g) ⇄ N2O4(g)

IF A LARGE QUANTITY OF ARGON IS ADDED TO THE CONTAINER IN WHICH THIS EQUILIBRIUM IS TAKING PLACE, IN WHAT DIRECTION WILL THE EQUILIBRIUM SHIFT?

4. NH4OH(aq) ⇄ NH3(g) + H2O(l)

IN WHAT DIRECTION WILL THE EQUILIBRIUM SHIFT IF AMMONIA IS REMOVED FROM THE CONTAINER AS SOON AS IT IS PRODUCED? 5. The following system is at equilibrium. In which direction (right or left) will the equilibrium position shift with the following changes?

3NO(g) <--> N2O(g) + NO2(g) + 154.9 kJ

(right, left, or no effect)

1. a. Lowering the temperature?
2. b. Raising the temperature?

c. Adding more N2O?

1. d. Adding more NO?
2. e. Removing some N2O?
3. f. Adding a catalyst?
4. g. Increasing the volume?

BALANCE EQUATIONS

1) Explain why amount ofactivation energy required will not affect the Keq of a reactionattaining equilibrium.

2) 2) Consider the followingequilibrium: NO_2(g)<-> N₂O_4(g)

Inwhat direction will the equilibrium shift ifN₂O_4(g) is removed from the container as soonas it is produced? Why?

3) 3) Consider the followingequilibrium: NH₄OH_(aq)<-> NH_3(g) +H₂O_(l)

Ifa large quantity of argon is added to the container in which thisequilibrium is taking place, in what direction will the equilibriumshift and WHY?

4) 4) Consider thefollowing equilibrium: NO_2(g) <->N₂O_4(g)

Write the K_eq and Q expressions for thisreaction

5) Why can the hydrogen ion concentrationin an extremely weak acid, e.g.,CH₃CH₂OH(pKa=38.0), never get less thanpH7?

6) 6) Consider the followingequilibrium Ag₂O(s) <-> Ag(s) +O₂(g)

Write the K_p. expression for thisreaction

QUESTION 7

Consider the following reaction at equilibrium. What effect will increasing the pressure of the reaction mixture have on the system?

CuS(s) + O₂(g) ⇌ Cu(s) + SO₂(g)

The equilibrium constant will increase.

No effect will be observed.

The equilibrium constant will decrease.

The reaction will shift to the right in the direction of products.

The reaction will shift to the left in the direction of reactants.

QUESTION 8

Consider the following reaction at equilibrium. What effect will increasing the temperature have on the system?

Fe₃O₄(s) + CO(g) ⇌ 3 FeO(s) + CO₂(g) ΔH°= +35.9 kJ

The equilibrium constant will increase.

The reaction will shift to the right in the direction of products.

The reaction will shift to the left in the direction of reactants.

The equilibrium constant will decrease.

No effect will be observed.