The vapor pressure of pure water at 295 k is 2614.5 pa. the vapor forms an ideal gas.1) in some oil, the equilibrium concentration of water molecules is only 1% as large as in pure water. suppose that the pure water is covered with a layer of that oil. what's the equilibrium vapor pressure of water above the oil layer? answer = 2614.5 pa2) what's the vapor pressure of water at 295 k above a sugar solution in which 1/32 of the molecules are sugars, not water? you may assume that the sugar is an ideal solute, as in the problem on sugar water chemical potential. for ideal solutes the effect on the chemical potential of the water comes entirely from the dependence of the solute entropy on the volume of water available to it.