Number of mole of solute in a solution can be calculated by using the following formula
\[n = \frac{{MV}}{{1000}}\]
n = number of mole of solute
M = molaruty of the solution
V = volume of the solution in cm3
Example:
How many moles of zinc sulphate is present in 200cm3 of 0.1 mol dm-3 zinc sulphate solution?
Answer:
Molarity, M = 0.1 mol dm-3
Voloume, V = 200cm3
\[\begin{gathered}
n = \frac{{MV}}{{1000}} \hfill \\
n = \frac{{(0.1)(200)}}{{1000}} \hfill \\
n = 0.02mol \hfill \\
\end{gathered} \]