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Question

Question: State true or false. For the same solution, the elevation in boiling point has higher values than ...

State true or false.
For the same solution, the elevation in boiling point has higher values than depression in freezing point.
(A) True
(B) False

Explanation

Solution

Hint : Colligative properties: These are properties of solutions that rely on the ratio of the number of solute particles to the number of solvent molecules in a solution.

Complete step-by-step answer:
Elevation in boiling point: The boiling point of a liquid is the temperature at which its vapor pressure is equal to the atmospheric pressure. The vapor pressure of a liquid is lowered when a non-volatile solute is added to it. Hence, the temperature of the solution when its vapor pressure will be equal to atmospheric pressure will be higher than the temperature of the pure solvent. The difference in the boiling point of the solution and the boiling point of the pure solvent is known as the elevation of the boiling point.
Depression in freezing point: Freezing point depression is a colligative property seen in solutions that outcomes from the introduction of solute molecules to a solvent. The freezing points of solutions are all less than that of the pure solvent and are directly proportional to the molality of the solute.
For the same solution depression in freezing point has higher values as compared to the elevation in boiling point. This is because the value of Kf{ K }_{ f } (molal freezing point depression constant) for a given solvent is higher than the value of Kb{ K }_{ b } (molal elevation in boiling point constant) for the same solvent.
Hence, the given statement is not correct.
The correct option is B.

Note: The possibility to make a mistake is that you may confuse between Kb{ K }_{ b } and Kf{ K }_{ f }. As Kb{ K }_{ b } is the molal elevation in boiling point constant or ebullioscopic constant whereas Kf{ K }_{ f } is molal freezing point depression constant or cryoscopic constant.