12.1 The general properties of the s-block elements The alkali metals (IA )nsl Li,Na,K,Rb,Cs,Fr The alkaline metals (IIA )ns2 Be,Mg,Ca,Sr,Ba,Ra They are all active metals§12.1 The general properties of the s-block elements The alkali metals (IA )：ns1 Li, Na, K, Rb, Cs, Fr The alkaline metals (IIA )：ns2 Be, Mg, Ca, Sr, Ba, Ra They are all active metals