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Statement-1: The molality of pure ethanol is less than that of pure water. Statement-2: The density of ethanol is less than the density of water. [Given: density of ethanol = 0.789 g/mL; density of water = 1 g/mL]

1. Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.
2. Statement-1 is true, Statement-2 is true but Statement-2 is NOT the correct explanation of Statement-1.
3. Statement-1 is false, Statement-2 is true.
4. Statement-1 is true, Statement-2 is false.

Correct answer: Statement-1 is true, Statement-2 is true but Statement-2 is NOT the correct explanation of Statement-1.

Solution

Molality of pure ethanol = 1000/46 = 21.7 m, water = 1000/18 = 55.5 m, so Statement-1 is true. Statement-2 (about density) is true but is not the reason; molality depends on molar mass, not density.

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