Give a brief explanation of the carbonate,sulphate,and nitrate compounds of alkaline earth metal elements.

(N/A) Salts of Oxoacids: The alkaline earth metals form salts of oxoacids,including: $(a)$ Carbonates,$(b)$ Sulphates,and $(c)$ Nitrates.
$(a)$ Carbonates: Carbonates of alkaline earth metals are insoluble in water and are precipitated by adding sodium or ammonium carbonate to a solution of a soluble salt of these metals. The solubility of carbonates in water decreases as the atomic number of the metal ion increases. All carbonates decompose on heating to give carbon dioxide and the metal oxide. $BeCO_{3}$ is unstable and can only be stored in an atmosphere of $CO_{2}$. Thermal stability increases with increasing cationic size.
$(b)$ Sulphates: The sulphates of alkaline earth metals are white solids and are stable to heat. $BeSO_{4}$ and $MgSO_{4}$ are readily soluble in water; the solubility decreases from $CaSO_{4}$ to $BaSO_{4}$. The high hydration enthalpies of $Be^{2+}$ and $Mg^{2+}$ ions overcome the lattice enthalpy,making their sulphates soluble.
$(c)$ Nitrates: Nitrates are prepared by dissolving carbonates in dilute nitric acid. $Mg(NO_{3})_{2}$ crystallizes with six molecules of water,while $Ba(NO_{3})_{2}$ crystallizes as an anhydrous salt. This reflects a decreasing tendency to form hydrates with increasing size and decreasing hydration enthalpy. All nitrates decompose on heating to form the oxide: $2M(NO_{3})_{2} \rightarrow 2MO + 4NO_{2} + O_{2}$ (where $M = Be, Mg, Ca, Sr, Ba$).