Question

The density of $1$ M solution of $NaCl$ is $1.0585gm{l}^{-1}$. The molality of the solution is :

• A. $1.0585$
• B. $1.00$
• C. $0.10$
• D. $0.0585$

Answer 1

Answer: (B)

$1.00$

The relation between density and molality is given by-

$d=M(\frac{MW}{1000}+\frac{1}{m})\Rightarrow 1.0585=1(\frac{58.5}{1000}+\frac{1}{m})$
$\therefore m=1$