WHAT IS THE SOLUBILITY OF 0.80m AT 25C

Question

At a 25°C the solubility of CO₂ in water is 0.13 M when the partial pressure is 1.5

atm. What partial pressure (in atm) of CO₂ would give a solubility of 0.080 M at 25°C?

Answer 1

According to Henry's law, the solubility of a gas is proportional to the partial pressure of the gas above the solution or C = k x P. To find k, substitute the 0.13 M for concentration and 1.5 atm for P and solve for k.

k = 0.13 / 1.5 = 0.087 M/atm

To find the partial pressure to give 0.08 M, use P = C / k = 0.08 / 0.087 = 0.92 atm.