Question

The following question consist of two statements. Mark the answer as follows.
(A) If both statements are CORRECT, and Statement II is the CORRECT explanation of Statement I.
(B) If both statements are CORRECT, and Statement II is CORRECT the CORRECT explanation of Statement I.
(C) If Statement I is CORRECT, but Statement II is INCORRECT.
(D) If Statement I is INCORRECT, but Statement II is CORRECT.

Statement I: Molarity and molality for very dilute aqueous solution is approximately equal.
Statement II: For all aqueous solutions, total mass of solvent is approximately equal to total volume of solution.

• A. (B)
• B. (D)
• C. (A)
• D. (C)

Answer 1

The correct option is D (C)

Molarity and molality for very dilute aqueous solution is approximately equal, this statement is correct only for the very dilute solution.
This means: molarity of a solution = molality of that solution, if the solution is highly diluted or contains a very high volume of solvent because for very dilute aqueous solution, the volume of solution is nearly equal to the mass of solvent because the density of water is almost equal to $1.0gm{L}^{-1}$.
Hence, statement II is wrong and thus total mass of solvent may or may not be equal to the total volume of solution.