Question

How many liters of a 0.215 M MgCl2 solution are needed to obtain 0.015 moles of MgCl2?

Answer 1

Concentration of \(\mathrm{MgCl}_{2}\) solution \(=0.215 M=0.215 \mathrm{~mol} / \mathrm{L}\) No of moles of \(\mathrm{MgCl}_{2}=0.015 \mathrm{~mol}\)

$$ \begin{aligned} \text { Volume of solution } &=0.015 \mathrm{~mol} \mathrm{MgCl}_{2} \times \frac{1 \mathrm{~L}}{0.215 \mathrm{~mol} \mathrm{MgCl}_{2}} \\ &=0.0698 \mathrm{~L} \\ &=0.070 \mathrm{~L} \end{aligned} $$