Consider the following exothermic reaction \(2SO_{2(g)} + O_{2(g)} = 2SO_{3(g)}\) . If the temperature of the reaction is reduced from 800ºC to 500ºC, and no other change takes place, then

A.

the reaction rate increases

B.

concentration of SO3 decreases

C.

concentration of SO3 increases

D.

SO2 gas becomes unreactive

E.

O2 gas becomes unreactive

Correct answer is C

reducing the temperature from 800ºc to 500ºc will favour forward reaction according to Le Chatelier's principle hence the concentration of \(SO_3\) increases.