Azeotropes
Properties of solution affected by vapour pressure
Azeotropes
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Azeotropes are binary mixturespossessing the same synthesis in fluid , vapor stage and boiling stage at a steady temperature .
The components of azeotropic mixtures are separated by fractional distillation .
Azeotropes can be broadly categorized into two types- 1 . Minimum boiling azeotrope
The solutions showing positive deviation from Raoult ’ s law . For instance , solution of ethanol and water on fractional distillation results in a solution containing approximately 95 % by volume of ethanol .
2 . Maximum boiling azeotrope .
The solutions showing negative deviation from Raoult ’ s law . For instance , solution of nitric acid and water has the approximate arrangement , 68 % nitric corrosive and 32 % water by mass , with a breaking point of 393.5 K .
Properties of solution affected by vapour pressure
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Vapour pressure of solution decreases on addition of a non-volatile solute to a volatile solvent .
Properties of solutions affected by the decrease of vapour pressure includes-
1 . Relative lowering of vapour pressure of the solvent 2 . Depression of freezing point of the solvent 3 . Elevation of boiling point of the solvent and 4 . Osmotic pressure of the solution .
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These properties of solution depend on the number of solute particles present in the solution regardless of their nature relative to the total number of particles present in the solution . These