1-Henrys law constant KH for oxygen in water at 25 oC is 4.3x104 atm (see eq. 7.30). Calculate the concentration of oxygen (mol.L1) in water in equilibrium with atmospheric oxygen (pO2 = 0.2 atm) at 25 oC.

2-Calculate the vapour pressure lowering at 20 ^oC of a solution of a non-electrolyte in water that has a freezing point depression of 0.372 ^oC. The vapour pressure of water at 20 ^oC, p^o = 17.54 mm Hg