1. The problem statement, all variables and given/known data Knowing that the vapour pressure of water at 25 C is 24 mm Hg, that the oxygen composition of air is 20% v/v and that the solubility of oxygen in water is 31.6 mL/L, demonstrate that the 100% O2 (oxygen) saturation is 0.75 umol (micromoles) 2. Relevant equations pV=nRT ? 3. The attempt at a solution I tried using pV=nRT taking into account the vapour pressure and getting a solution that was not 0.75 umol. I also attempted a ratio between the 31.6 mL/L as well as the density but I don't really know where to go from there. Any help at coming to the solution would be much appreciated!