Formation of $\mathrm{ClF}_3$ from $\mathrm{Cl}_2$ and $\mathrm{F}_2$ is an exothermic process. The

Question

Formation of $\mathrm{ClF}_3$ from $\mathrm{Cl}_2$ and $\mathrm{F}_2$ is an exothermic process. The equilibrium system can be represented as $\mathrm{Cl}_{2(\mathrm{~g})}+3 \mathrm{~F}_{2(\mathrm{~g})} \rightleftharpoons 2 \mathrm{ClF}_3 ; \Delta H=-329 \mathrm{~kJ} \mathrm{~mol}^{-1}$
 Which of the following will increase quantity of $\mathrm{ClF}_3$ in the equilibrium mixture?
A. Increase in temperature
B. Decrease in pressure
C. Addition of $\mathrm{Cl}_2$
D. Decrease in temperature
E. Addition of $\mathrm{ClF}_3$
F. Increase in pressure

Professor PC Thomas Classes · Answer

(d) : For an exothermic reaction, decrease in temperature shifts the equilibrium to forward direction. Also, in the given reaction, $\Delta n_g$ is negative thus, increase in pressure favours forward reaction. Addition of $F_2$ also shifts the reaction in forward direction resulting increase in quantity of $\mathrm{ClF}_3$.