Question

3.0 g of a salt of molecular weight 30 is dissolved in 250 ml water. The molality of solution is :

• A. 0.4
• B. 0.2
• C. 0.8
• D. 0.6

Answer 1

The correct option is A 0.4

The expression for the molality of solution is :

$=\frac{\text{Number of moles of solute}}{\text{Weight of solvent in Kg}}=\frac{\text{Weight of solute}}{\text{Molar mass}}\times \frac{1000}{\text{Weight of solvent in Kg}}=\frac{3}{30}\times \frac{1000}{250}=0.4M$.