Properties such as boiling point, freezing point and vapour pressure of a pure solvent
Channel: Doubtnut
Date: 12/04/2020

Properties such as boiling point, freezing point and vapour pressure of a pure solvent change when solution molecules ae added to get homogeneous solution. These are called colligative properties. Application colligative properties are very useful in day-to-day life. One of its example is the use of ethylene glycol and water mixture as anti-freezing liquid in the radiator of automobiles   A solution `M` is prepared by mixing ethanol and water. The mole fraction of ethanol in the mixture is `0.9` Given: Freezing point depression of water `(K_(f)^("water"))=1.86K kg "mol"^(-1)`   Freezing point depression constant of ethanol `(K_(f)^("ethanol")=2.0K kg "mol"^(-1)`   Boiling point elevation constant of water `(K_(b)^("water")=0.52K kg "mol"^(-1)`   Boiling point elevation constant of ethanol `(K_(b)^("ethanol")=1.2K kg "mol"^(-1)`   Standard freezing point of water`=273K`   Standard freezing point of ethanol`=155.7K`   Standard boiling point of water `=373K`   Stadndard boiling point of ethanol `=351.5K`   Vapour pressure of pure water `=32.8mm Hg `   Vapour pressure of pure ethanol`=40mm Hg`   Molecular weight of water `=18 g "mol"^(-1)`   Molecular weight of ethanol `=46g "mol"^(-1)`   In aswering the following questions, consider the solution to be ideal dilute solutions and solutes to be non volatile and non-dissociative.    The freezing point (in `.^(@)C`) of a solution containing `0.1g` of `K_(3)[Fe(CN)_(6)]` (Mol. Wt. `329`) in `100g` of water `(K_(f)=1.86K kg "mol"^(-1)` is :