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Question
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be ______.
Options
doubled
halved
tripled
unchanged
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Solution
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be unchanged.
Explanation:
The molal depression constant Kf is a property of the solvent only and is defined as
ΔTf = Kf m
Here, Kf depends on the solvent’s nature and not on the solute concentration.
So, even if the molality is doubled, the value of Kf remains unchanged.
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