Question

1.For the reaction at equilibrium 2 SO3↔ 2 SO2 + O2 (∆Horxn= 198 kJ/mol), if we increase the reaction temperature, the equilibrium will (1 point ) *

No shift

None of the above

Question lacks sufficient information

Shift to the right

2.

For the equilibrium reaction 2 SO2(g) + O2(g) ↔ 2 SO3(g), ∆Horxn = -198 kJ/mol. Which one of these factors would cause the equilibrium constant to increase? (1 point ) *

Add a catalyst

Decrease the temperature

None of the above

Remove O2 gas

Answer 1

According to Le-Chatelier's principle, if a system at equilibrium is subjected to change in concentration, temperature, pressure, and volume, then the system shifts in the direction to counteract the change. For exothermic reactions, when temperature is increased, the reaction moves in the backward direction and vice-versa. For endothermic reactions, when temperature is increased, the reaction moves in the forward direction and vice-versa. 1) The given reaction is: 2803 = 2802 +02 (AH2n = 198 kJ/mol) This reaction is endothermic, if the reaction temperature is increased the reaction shifts to the right 2) The given reaction is: 280+02 72503 (AHan =-198kJ/mol)

Addition of catalyst has no effect on the equilibrium constant. Decrease in temperature for exothermic reaction, shifts the reaction in forward direction, and hence, increase the value of equilibrium constant. Removal of reactant has no effect on the value of equilibrium constant. O