Be sure to answer all parts. Consider the reaction 2SO2(g) + O2(g) ⇌ 2SO3(g)ΔH = −198.2 kJ/mol How would the concentrations of SO2, O2, and SO3 at equilibrium change if we were to (a) increase the temperature? [SO2]: The concentration increases. The concentration decreases. There is no change. [O2]: The concentration increases. The concentration decreases. There is no change. [SO3]: The concentration increases. The concentration decreases. There is no change. (b) increase the pressure and decrease the volume? [SO2]: The concentration increases. The concentration decreases. There is no change. [O2]: The concentration increases. The concentration decreases. There is no change. [SO3]: The concentration increases. The concentration decreases. There is no change. (c) add a catalyst? [SO2]: The concentration increases. The concentration decreases. There is no change. [O2]: The concentration increases. The concentration decreases. There is no change. [SO3]: The concentration increases. The concentration decreases. There is no change.

For an exothermic reaction, increase in temperature decreases the concentration of products and increases the concentration of reactants since increase in temperature shifts the equilibrium position to the left hand side.

Increase in pressure and decrease in volume will shift the equilibrium position towards the right hand side which means more SO3 in the system.

Catalyst increases the rate of forward and reverse reaction simultaneously hence at equilibrium, the concentration of reactants and products remain unchanged.