Question

The density of $10.0\%$ by mass $KCl$ solution in water is $1.06gc{m}^{-3}.$ Its molarity is

• A. 1.489 M
• B. 1.420 M
• C. $1.420molk{g}^{-1}$
• D. $1.489molk{g}^{-1}$

Answer 1

Answer: (B)

Mass of 1 litre solution $=1000\times 1.06=1060g$

Amount of $KCl$ in solution $=1060\times \frac{10}{100}=106g$

Molarity $=\frac{106}{74.5}\times \frac{1000}{1000}=1.42M$