Question

In a vessel $N_2,H_2$ and $N{H}_3$ are at equilibrium. Some helium gas is introduced into the vessel so that total pressure increases while temperature and volume remain constant. According to Le Chatelier's principle, the dissociation of $N{H}_3$:

• A. increases
• B. decreases
• C. remains unchanged
• D. equilibrium is disturbed.

Answer 1

Answer: (C)

remains unchanged

$N_2+3H_2\rightleftharpoons 2N{H}_3$

According to Lechatelier's principle, the dissociation of ammonia remains unchanged, when total pressure increases. Only when there is a change in partial pressure, the equilibrium is effected.