Question

For the reaction, $H_2\left(g\right)+I_2\left(g\right)\rightleftharpoons 2HI\left(g\right)$ equilibrium constant, $K_p$ changes with:

• A. total pressure
• B. catalyst
• C. amount of $H_2$ and $I_2$ present
• D. temperature

Answer 1

The correct option is A total pressure

$H_2+I_2\rightleftharpoons 2HI{K}_p=K_n{\left(\frac{P}{n}\right)}^{\Delta n_g}{K}_p=\frac{{\left[P_{HI}\right]}^2}{\left[P_{H_2}\right]\left[P_{I_2}\right]}P=\frac{nRT}{V}{K}_p=\frac{{\left[n_{HI}\right]}^2}{\left[n_{H_2}\right]\left[n_{I_2}\right]}{\left(\frac{RT}{V}\right)}^{\Delta n_g}{K}_p\propto P$

Thus, $K_p$ changes with total pressure.