Question

A solution is prepared by dissolving 20 g of naoh in 100 g of wate. calculate the molality of solution

Answer 1

Number of moles of NaOH = given mass/molar mass = 20/40 = 0.5

Mass of solvent = 100 grams = 0.1 kg

→ Molality = Number of moles/mass of solvent (in kg)

→ Molality = 0.5/0.1 = 5

∴ The molality of the solution is 5

Hope it helps!!

Answer 2

Molality = weight of NaOH X 1000 / (Volume of water X Equivalent weight of NaOH)

Molality = 20 X 1000 / (100 X 40) = 5 M

The molality of solution is 5 M