Property Change

The vapor pressure of a liquid is the equilibrium pressure of gas molecules from that liquid above the liquid itself. By adding a solute the vapor water pressure depression is the lowering of a solvent’s vapor pressure . Vapor pressure is a solvent’s ability to evaporate or boil off surface molecules. Sometimes, a solvent cannot evaporate easily, when a solute is added. This happens because the solute particles hinder the solvent’s natural behaviors by getting in the way of the solvent's molecules and their inter molecular forces.