Question

why is vapour pressure of solution of glucose in water lower than that of water?
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Answer 1

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☞The vapour pressure of an aqueous solution of glucose lower than that of water. It is because in glucose solution, the surface of liquid consists of both solute and solvent molecules, therefore, the fraction of surface covered by the solvent molecules gets reduced.

Answer 2

Answer:

A part of water surface is occupied by non- volatile glucose molecules. This decreases the effective surface area for the vaporization of water molecules.

Consequently, the vapour pressure of solution of glucose in water is lower than that of water.