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The vapour pressure of a solution is alw...

The vapour pressure of a solution is always less than of the pure solvent, when the temperature of both the solution and solvent are the same, with the same external pressure acting over them. Explain.

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(i) relation between the vapour pressure of the liquid and its intermolecular forces of attraction
(ii) comparison of the constituents of solution and pure solvent
(iii) comparison of the intermolecular force of attraction existing in the solution and that in the existing pure solvent
(iv) effect on vapour pressure
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Vapour pressure of a solvent containing nonvolatile solute is:

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