1. The problem statement, all variables and given/known data 'Look up the density and vapour pressure of water at 25°C, and use the ideal gas law to calculate Vliq as a fraction of Vg for one mole of water at 25°C' Ok so, Density of water at 25°C & 1atm is: 0.997 g/cm³. The vapour pressure of water at 25°C and 1atm is: 3.1691 kPa 2. Relevant equations The ideal gas law: PV=nRT Also, I think perhaps the Clausius-Claperon equation might be used?! 3. The attempt at a solution I think the question is a little ambiguous, so I am unsure of how to approach this question. For a start, I can use the ideal gas equation to work out the volume of one mole of water vapour at 25°C and 1atm: V=nRT/P= (1mole)x(8.314J/Mol.K)x(298K)/101,325Pa= 0.0245m³ However, i'm stuck now as to what is the next logical step!!!