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Statement-1: For a very dilute aqueous solution, molarity and molality have nearly the same numerical value. Statement-2: In any very dilute aqueous solution, the mass of solvent (in g) equals the volume of the solution (in mL). Choose the correct option.

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 true, Statement-2 is false.
4. Statement-1 is false, Statement-2 is true.

Correct answer: Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.

Solution

For dilute aqueous solutions density ~ 1 g/mL and the solute mass is negligible, so 1 L of solution ~ 1 kg of water; this is exactly why molarity and molality coincide, making Statement-2 the correct explanation.

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