Question

$40$g MgO dissolves in $H_{2}O$ to form $200$ ml of solution, if density of solution is $1.5$g/ml.

Calculate $\%$ w/v.

Answer 1

$MgO$ is solute & $H_{2}O$ is solvent

Weight of solvent $=40g$ volume of solution $=200ml$

$\%w/v=\frac{\text{weight of solute in gm}}{\text{volume of solution in ml}}\times 100$

$\%w/v=\frac{40}{200}\times 100=20\%$