Question

H₂S, a toxic gas with rotten egg like smell, is used for the qualitative analysis. If the solubility of H₂S in water at STP is 0.195 m, calculate Henry’s law constant.

Answer 1

It is given that the solubility of H₂S in water at STP is 0.195 m, i.e., 0.195 mol of H₂S is dissolved in 1000 g of water.

Moles of water

= 55.56 mol

∴Mole fraction of H₂S, x

= 0.0035

At STP, pressure (p) = 0.987 bar

According to Henry’s law:

p = K_Hx

= 282 bar