Question

At certain temperature, a $10$ lit vessel contains $0.4$ mole $H_2$, $0.4$ mole $I_2$ and $0.1$ mole $HI$ at equilibrium. Then $K_p$ for $H_2+I_2\rightleftharpoons 2HI$ is:

• A. $16$
• B. $0.0625$
• C. $4$
• D. data insufficient

Answer 1

Answer: (B)

$0.0625$

The given reaction is :-

$H_2+I_2\rightleftharpoons 2HI$

Now, partial pressure extered by gas at constant temperature & volume $\alpha$ no. of moles of gas

$\Rightarrow p\alpha n$

Now, $K_P=\frac{{\left(pHI\right)}^2}{{pH}_2.{pI}_2}$

$=\frac{{\left(0.1\right)}^2}{0.4\times 0.4}=\frac{1}{4\times 4}=\frac{1}{16}=0.0625$