Question

HI was heated in a sealed tube at ${400}^{\circ }C$ till the equilibrium was reached. HI was found to be $22\%$ decomposed. The equilibrium constant for dissociation is:

• A. 0.282
• B. 0.0296
• C. 0.0199
• D. 1.99

Answer 1

The correct option is C 0.0199

$2HI\rightleftharpoons H_2+I_2$
Initial 2
Dissociated 0.44
Formed 0.22 0.22
Remaining 1.56
$K_c=\frac{\left[H_2\right]\left[I_2\right]}{[HI{]}^2}=\frac{(0.22\times 0.22)}{(1.56{)}^2}=0.01988$