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If molality of the dilute solutions is doubled, the value of molal depression constant (Kf) will be:

1. halved
2. tripled
3. unchanged
4. doubled

Correct answer: tripled

Solution

The molal depression constant (Kf) is inversely proportional to the molality of the solution, so if the molality is doubled, Kf will be halved, and if Kf is halved, it will be tripled.

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