Using extended Wilson model to study the relationship between critical relative humidity and solubility of electrolytes

Based on thermodynamic principle, the critical relative humidity of electrolytes is closely related to their solubility.  The authors explored the relationship theoretically and calculated critical relative humidity  of 21 electrolytes from their solubility in the light of Raoult’s law and extended Wilson model.  The results     indicate that the critical relative humidity values calculated by Raoult’s law can not accord with the reported ones and there is a systematic error in the high concentration range; while these calculated by extended Wilson model are comparable to the reported ones.