Question

A.) If the temperature is decreased and some C is added, how does this affect the amount of A present at equilibrium for the following reaction?
A(g) + B(g) ↔ 2 C(g) + D(g)           ΔH° = -80 kJ

	Cannot be predicted.
	The amount of A will not change.
	The amount of A will decrease.
	The amount of A will increase.

B.) How does an increase in temperature affect the equilibrium concentration of the SO₂ and the equilibrium constant for the following reaction?
SO₂(g) ↔ S(s) + O₂(g)           ΔH° = 297 kJ

	[SO2] will increase and the equilibrium constant will increase.
	[SO2] will decrease and the equilibrium constant will increase.
	[SO2] will increase and the equilibrium constant will decrease.
	[SO2] will decrease and the equilibrium constant will decrease.

C.) How would you change the volume of the reaction container that holds the following reaction in order to increase the yield of SF₆?
S(s) + 3 F₂(g) ↔ SF₆(g)

	Increase the volume of the container.
	Cannot be predicted.
	Do not change the volume of the container.
	Decrease the volume of the container.

D.) How does an increase in temperature affect the equilibrium concentration of C and the equilibrium constant for the following reaction?
2 A(g) + B(g) ↔ 3 C(g) + D(g)           ΔH° = - 100 kJ

	[C] will decrease and the equilibrium constant will increase.
	[C] will decrease and the equilibrium constant will decrease.
	[C] will increase and the equilibrium constant will increase.
	[C] will increase and the equilibrium constant will decrease.

Answer 1

A) The reaction is exothermic. Therefore, a decrease in temperature will move the reaction in forward direction. Adding C will move the reaction in Backward direction. We do not know the magnitudes of movement of forward and backward direction. Hence we cannot determine the net result. Therefore the answer is cannot be predicted

B) The reaction is endothermic and an increase in temperature will favor forward reaction. Therefore reaction moves in forward direction decreasing SO2.

[SO₂] will decrease and the equilibrium constant will increase.

C) Decrease the volume of the container.

D) [C] will decrease and the equilibrium constant will decrease.