Question

For the reaction, $N_2\left(g\right)+3H_2\left(g\right)\rightleftharpoons 2{NH}_3\left(g\right)$, the unit of K is :

• A. $L{mol}^{-1}$
• B. $L^2{mol}^{-2}$
• C. $mol{L}^{-1}$
• D. no units

Answer 1

Answer: (B)

$L^2{mol}^{-2}$

$N_2\left(g\right)+3H_2\left(g\right)\rightleftharpoons 2{NH}_3\left(g\right)$

$K=\frac{{\left[{NH}_3\right]}^2}{\left[N_2\right]{\left[H_2\right]}^3}=\frac{{\left[\frac{mol}{L}\right]}^2}{\left[\frac{mol}{L}\right]{\left[\frac{mol}{L}\right]}^3}$

$K={\left[\frac{mol}{L}\right]}^{-2}=L^2{mol}^{-2}$