Question

If the value of equilibrium constant $K_c$ for the reaction, $N_2 + 3H_2 \rightleftharpoons 2NH_3$ is $7$. The equilibrium constant for the reaction $2N_2 + 6H_2 \rightleftharpoons 4NH_3$ will be

• A. $49$
• B. $7$
• C. $14$
• D. $28$

Answer 1

Answer: (A)

$N _{2}+3 H _{2} \rightleftharpoons 2 NH _{3}$, given that $K _{ c }=7$
$2 N _{2}+6 H _{2} \rightleftharpoons 4 NH _{3}$
If the first reaction is multiplied by 2 , the equilibrium constant becomes square of the first reaction $K _{ c }$.
So, $K _{ c }^{\prime}= K _{ c }^{2}=7^{2}=49$