(a(i))[1]
From the mass spectrum, fill in the table with the relative abundances of the three isotopes: $^{24}\text{Mg}$, $^{25}\text{Mg}$ and $^{26}\text{Mg}$.
(a(ii))[1]
Use the values from (i) to calculate the relative atomic mass, $A_r$, of magnesium to two decimal places.
(b(i))[3]
Describe and explain how the thermal stabilities of the Group II nitrates change down the group.
(b(ii))[1]
Suggest an equation for what happens when $\text{LiNO}_3$ is heated.
(b(iii))[1]
Suggest why the Group I nitrates other than $\text{LiNO}_3$ do not decompose in this way when heated.