Question

For the reaction $N{H}_{4}H{S}_{\left(s\right)}\rightleftharpoons N{H}_{3\left(g\right)}+H_2{S}_{\left(g\right)}$, started with $N{H}_{4}H{S}_{\left(s\right)}$ only. observed equilibrium pressure of the mixtures is $1.2$ atm at certain temperature, what is the $K_p$ of the reaction?

• A. $0.6$
• B. $1.2$
• C. $0.36$
• D. $1.44$

Answer 1

The correct option is C $0.36$

$△n=2-0=2$${NH}_4{HS}_{\left(S\right)}\rightleftharpoons {NH}_{3\left(g\right)}+H_2{S}_{\left(g\right)}$

$△n=2-0=2$

$X_{{NH}_3}=\frac{1}{2}{X}_{H_{2}S}=\frac{1}{2}$

$K_P=P_{{NH}_3}\times P_{H_{2}S}$

$=\frac{1}{2}\times 1.2\times \frac{1}{2}\times 1.2=0.36$