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The density of 'x' M solution ('x' molar) of NaOH is 1.12 g mL⁻¹. while in molality, the concentration of the solution is 3 m (3 molal). Then x is (Given : Molar mass of NaOH is 40 g/mol)

1. (1) 3.5
2. (2) 3.0
3. (3) 3.8
4. (4) 2.8

Correct answer: (2) 3.0

Solution

To find the molarity (x) of the NaOH solution, we can use the relationship between molality and density. Given that the solution is 3 molal, this means there are 3 moles of NaOH per kilogram of solvent. Using the density to convert the mass of the solution to volume, we can calculate that the molarity is approximately 3.0 M.

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