Question

An aqueous solution of $Fe{Cl}_3$ (molar mass =$162g{mol}^{-1}$) has a density of $1.1$ g/mL and contains $20$% $Fe{Cl}_3$. What is molarity of this solution?

• A. 0.28 M
• B. 1.35 M
• C. 2.17 M
• D. 1.97 M

Answer 1

The correct option is B 1.35 M

Here, assume the mass of the solution is $100$g.

$M=\frac{w\times 1000}{m\times V}$ $\because (V=\frac{w}{d}=\frac{100}{1.1}mL)$

$=\frac{20\times 1000}{162\times \frac{100}{1.1}}=1.35M$

$M=1.35M$

Hence, the correct option is $B$