Question

$H_{2}S$, a toxic gas with rotten egg like smell, is used for the qualitative analysis. If the solubility of $H_{2}S$ in water at STP is 0.195 m, Calculate Henry's law constant.

• A. 282.0 bar
• B. 324.8 bar
• C. 462.9 bar
• D. 534.8 bar

Answer 1

The correct option is A 282.0 bar

$1kg$ of solvent contains $\frac{1000}{18}=55.55$ moles.

Mole fraction of $H_{2}S$ is $\frac{0.195}{0.195+55.55}=\frac{0.195}{55.475}=0.0035$

Pressure of $H_{2}S$ =$\frac{0.987}{0.0355}=282bar$

( at STP pressure is 0.987bar.)