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A substance H₂X with a molecular mass of 80 g is mixed into a liquid with a density of 0.4 g/ml. If the volume remains constant during dissolution, what is the molality of a solution with 3.2 molarity?

1. 2
2. 8
3. 4
4. 6

Correct answer: 8

Solution

The correct answer is 8 because the molality of a solution is calculated by dividing the number of moles of solute by the mass of the solvent in kilograms, and given the molarity and density of the solution, we can determine the mass of the solvent and calculate the molality.

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