Alkali Metals are located in the first group in the periodic table. (Hydrogen is not alkali, be careful with that).
Alkaline Earth Metals are in group number two, right next to the Alkali Metals.
You have to look at the vertical groups ( 1 and 2).
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ALKALI METALS (AL) VS ALKALINE EARTH METALS (ALE).
Alkali Metals are soft, Alkaline Earth Metals are hard.
AL have only one electron in the last shell, ALE have 2.
AL present a low melting point, ALE high.
AL form hydroxides strongly basic, ALE hydroxides are less basic.
AL are more reactive than ALE
AL have +1 ionic charge in their compounds, ALE have +2 ionic charge in their compounds.