Question

When a non-electrolyte, non-volatile solute is dissolved in water, the observed depression in freezing point of water is 0.186 K. What is the molality of the solution if molal depression constant for water is 1.86 K kg mol⁻¹?

Options

• 0.001 m

• 0.01 m

• 0.1 m

• 1.0 m

Answer 1

0.1 m

Explanation:

m = `(Δ"T"_"f")/("K"_"f")`

= `(0.186  "K")/(1.86  "K kg mol"^-1)`

= 0.1 kg mol⁻¹

= 0.1 m