Question

If the density of methanol is $0.793\text{kg}{L}^{-1}$, what is its volume needed for making $2.5$ L of its $0.25$ M solution?

Answer 1

Mass of methanol required is

$M=\text{Volume of solution}\times \text{Molariy of solution}\times \text{Molar mass of methanol}$

$=2.5\times 0.25\times 32=20$ g.

Volume of methanol needed $=\frac{\text{mass}}{\text{density}}=\frac{20}{0.793}=25.22$ mL.