How do the alkali metals differ from the alkaline earth metals?
Alkali metals exist in pure form; alkaline earth metals appear in nature as compounds.
Alkali metals are much less reactive than alkaline earth metals.
Alkali metals are much harder than the alkaline earth metals.
Alkali metals have one valence electron and alkaline earth metals have two.
Alkali metals are located in group 1 of the periodic table, while alkaline earth metals are located in group 2.
Alkali metals have lower melting and boiling points than alkaline earth metals.
Alkali metals are softer and have lower densities compared to alkaline earth metals.
Alkali metals are more reactive with water and air than alkaline earth metals.