Le Chatelier's Principle

   1) Consider the following equilibrium, established in a 2-L flask at 30�C.

CO(g) + H₂O(g) CO₂(g) + H₂(g)     ΔH° = -41.2 kJ

What will happen to the concentration of CO if the temperature is increased?

(a) It will increase.

(b) It will decrease.

(c) It will not change.

 

   2) Consider the following equilibrium, established in a 3-L flask at 1227�C.

2SO₂(g) + O₂(g) 2SO₃(g)     K = 0.15

What will happen to the concentration of SO₃ if the concentration of SO₂ is increased?

(a) It will increase.

(b) It will decrease.

(c) It will not change.

   3) Consider the following equilibrium, established in a 3-L flask at 50�C.

NiO(s) + CO(g) Ni(s) + CO₂(g)     

Which direction will the equilibrium shift if the pressure is increased?

(a) To the right.

(b) To the left.

(c) The position of the equilibrium will not change.

   4) Consider the following equilibrium, established in a 1-L flask at 20�C.

Fe₃O₄(s) + CO(g) 3FeO(s) + CO₂(g)     ΔH° = 19 kJ

What will happen to the concentration of CO if the temperature is decreased?

(a) It will increase.

(b) It will decrease.

(c) It will not change.

   5) Consider the following equilibrium, established in a 1-L flask at 20�C.

Fe₃O₄(s) + CO(g) 3FeO(s) + CO₂(g)     ΔH° = 19 kJ

What will happen to the concentration of CO₂ if more Fe₃O₄ is added?

(a) It will increase.

(b) It will decrease.

(c) It will not change.

   6) Consider the following equilibrium, established in a 2-L flask at 50�C.

CS₂(g) + 4H₂(g) CH₄(g) + 2H₂S(g)     

If the pressure is increased, in which direction will the equilibrium shift?

(a) To the right.

(b) To the left.

(c) The position of the equilibrium will not change.

   7) Consider the following equilibrium, established in a 1-L flask at 20�C.

CO(g) + H₂O(g) CO₂(g) + H₂(g)     ΔH° = -41.2 kJ

What will happen to the concentration of CO₂ if the temperature is decreased?

(a) It will increase.

(b) It will decrease.

(c) It will not change.

    8) Consider the following equilibrium, established in a 2-L flask at 40�C.

CH₄(g) + 2H₂S(g) CS₂(g) + 4H₂(g)     

If the pressure is decreased, in which direction will the equilibrium shift?

(a) To the right.

(b) To the left.

(c) The position of the equilibrium will not change.