Raoult's law revisited: accurately predicting equilibrium relative humidity points for humidity control experiments

摘要

The equilibrium relative humidity values for a number of the most commonlyused precipitants in biological macromolecule crystallisation have beenmeasured using a new humidity control device. A simple argument in statisticalmechanics demonstrates that the saturated vapour pressure of a solvent isproportional to its mole fraction in an ideal solution (Raoult's Law). The sameargument can be extended to the case where solvent and solute molecules are ofdifferent size.