Question

In which of the following equilibrium reactions, the equilibrium would shift to the right if pressure is increased?

• A. $N_2+3H_2\leftrightharpoons 2N{H}_3$
• B. $H_2+I_2\leftrightharpoons 2HI$
• C. $H_2+C{l}_2\leftrightharpoons 2HCl$
• D. $N_2+O_2\leftrightharpoons 2NO$

Answer 1

The correct option is A $N_2+3H_2\leftrightharpoons 2N{H}_3$

In the reaction $N_2\left(g\right)+3H_2\left(g\right)\leftrightharpoons 2N{H}_3\left(g\right)$, the number of moles decreases in the forward reaction from $4$ to $2$. Also, the number of moles increases in the reverse reaction from $2$ to $4$.

When the total pressure is increased, the forward reaction will be favored as the forward reaction occurs with a decrease in the number of moles (according to Le-Chatelier's principle). Thus, the position of the equilibrium will shift towards the products.

Option $A$ is correct.