| Alkali metals | Alkaline earth metals |
| (i) All alkali metals except Li form ionic compounds. | (i) All alkaline earth metals except Be form ionic compounds. |
(ii) The solubility of oxides of al kali metals increases down the group.
The basic character of the ox ides increases down the group | (ii) The solubility of oxides of Mg, – Ca, Sr and Ba increases from Mg to Ba. BeO, however, is covalent and insoluble in water.
The basic character of oxides in creases from MgO to BaO. BeO is, however, amphoteric. |
| (iii) All alkali metals form oxo salts such as carbonates, sul phates and nitrates. | (iii) All alkaline earth metals form oxo salts such as carbonates, sulphates and nitrates. |
| (iv) Solubility of carbonates and sul phates increases down the group. | (iv) Solubility of carbonates and sul phates decreases down the group. |
| (v) Carbonates and sulphates of Li decompose on heating while the stability, of carbonates and sulphates of other metals in creases down the group. | (v) The carbonates and sulphates of alkaline earth metals all decom pose on heating but the tempera ture of their decomposition in creases down the group, i.e., their thermal stability increases. |
