Question

If at a particular temperature, the density of $18M{H}_{2}S{O}_4$ is $1.8$ g cm${}^{-3}$. Percentage concentration (%) by mass of solution is :

Answer 1

$Molarity=\frac{w_{solute}}{M_{solute}\times V\left(litre\right)}$

Let the volume of solution be 1 L.

$18=\frac{w_{solute}}{98\times 1}$

$w_{solute}=18\times 98gm$

% concentration by mass=$\frac{w_{solute}}{w_{solution}}\times 100$

Density of solution is 1.8g/${cm}^3$ or 1800g/L.

The volume of solution is 1 L.

So, weight of solution is 1800g.

% composition by mass $=\frac{18\times 98}{1800}\times 100=98$%