Concentrated sodium hydroxide is 19.4 M and has a density of 1.54 g/mL and a molar mass of 40.0 g/mol. What is the molality of concentrated NaOH

25.4 M

Explanation:

From the question, 19.4 M implies that there are 19.4 moles of NaOH in 1000ml solution.

Hence

Mass of the solution = density × volume

= 1000×1.54 = 1540 g

Mass of pure NaOH = 19.4 moles × 40g/mol = 776 g

Mass of water = 1540 - 776 = 764 g

Therefore;

Molarity of solution= 19.4/764 × 1000 = 25.4 M

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