Andelen Mg i MgCl2:
\[\text{andel} = \frac {m_\mathrm{1Mg-atom}}{m_\mathrm{1MgCl_2-enhet}} = \frac {24,31\mathrm{u}}{(24,31+35,45 \cdot 2)\mathrm{u}} = 0,25533032\]
Massa Mg i 2,00 g MgCl2:
\[2,00\mathrm{g} \cdot 0,25533032 = 0,51066064\mathrm{g} ≈ 0,511\mathrm{g}\]
