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Why the vapour pressure of saline solut...

Why the vapour pressure of saline solutions is lower than that of pure water ?

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(a) Vapour Pressure . Vapour pressure of a liquid (or solution) is the pressure exerted by its vapours in equilibrium with the liquid (on solution) at a particular temperature .
(b) The presence of non volatile solute in a solution reduces the escaping tendency of the solvent molecules into vapour phase because some of solute particles occupy the position of solvent molecules on liquid surface . This lowers the vapour pressure .
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