A mole is defined as the mass of substance containing the same number of fundamental units as the are atoms in carbon 12. The equation of finding the mole is [tex]n=\frac{m}{M}[/tex], where n is number of moles, m is mass of [tex]MgCl_2[/tex] and M is the relative formula mass of [tex]MgCl_2[/tex]
The formula mass of [tex]MgCl_2[/tex] is 95.11 g/mol
So [tex]n=\frac{m}{M} = \frac{323g}{95.11g/mol}= 3.40mol[/tex].
