Question

In which of the following equilibria, the position of the equilibrium shifts towards products, if the total pressure is increased?

• A. $N_2\left(g\right)+3H_2\left(g\right)\leftrightharpoons 2N{H}_3\left(g\right)$
• B. $I_2\left(g\right)+H_2\left(g\right)\leftrightharpoons 2HI\left(g\right)$
• C. $N_2\left(g\right)+O_2\left(g\right)\leftrightharpoons 2NO\left(g\right)$
• D. $N_2{O}_4\left(g\right)\leftrightharpoons 2N{O}_2\left(g\right)$

Answer 1

The correct option is A $N_2\left(g\right)+3H_2\left(g\right)\leftrightharpoons 2N{H}_3\left(g\right)$

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

When the total pressure is increased, the forward reaction will be favoured as the forward reaction occurs with decrease in the number of moles. Thus, the position of the equilibrium will shift towards products.