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The density of 2 M aqueous solution of NaOH is 1.28 g/cm³. The molality of the solution is [Given that molecular mass of NaOH = 40 g mol⁻¹]

1. 1.32m
2. 1.20m
3. 1.56m
4. 1.67m

Correct answer: 1.20m

Solution

To find the molality of the solution, we need to find the mass of the solvent (water) in kg and the number of moles of the solute (NaOH).

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