Question

An aqueous solution of non-electrolyte 'A' with molecular mass $60$ contains $6\,g$ in $500\, mL$ and has a density equal to $1.05 \,g \,mL^{-1}$. The molalityof solution is

• A. 1.25
• B. 0.19
• C. 0.25
• D. 0.3

Answer 1

Answer: (B)

0.19

Answer 2

Mass of solution = 500 $\times$ 1.05 = 525 g Mass of solvent = 525 - 6 = 519 g Molality = $\frac{6 \times 1000}{60 \times 519}$ = 0.192 M .