Alkali Metals: Comparison of groups Ι and ΙΙ.

Alkali metals are softer than alkaline earth metals.
Alkali metals will have an oxidation state of +1 while alkaline earth metals will have an oxidation state of +2. This is because alkali metals have one electron in their outer shell while alkaline earth metals have two.
Alkaline earth metals will react directly with nitrogen to form nitrides, while alkali metals will not.
Alkali metals will react with ammonia to form an amide, while alkaline earth metals will react with ammonia at a low temperature to form a hexamines.
Alkaline earth metal carbonates will decompose easily upon heating, while alkali metals are more stable.
Alkali metal nitrates will decompose evolving oxygen, while alkaline earth metal nitrates will evolve NO2 and O2.
Sulfates formed by alkali metals are very soluble, while sulfates of alkaline earth metals are not so soluble.
Alkali metal bicarbonates are less soluble than their carbonates, and vice versa for alkaline earth metal bicarbonates and carbonates.
Fluorides, carbonates, phosphates and oxalates of alkali metals are soluble, while those of alkaline earth metals are not.

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