What oxidation state (s) can the alkaline earth metals exhibit?

+2

Explanation:

Alkaline earth metals are present in group 2 of periodic table. There are six elements in second group. Beryllium, magnesium, calcium, strontium, barium and radium.

All have two valance electrons.

Electronic configuration of Beryllium:

Be = [He] 2s²

Electronic configuration of magnesium.

Mg = [Ne] 3s²

Electronic configuration of calcium.

Ca = [Ar] 4s²

Electronic configuration of strontium.

Sr = [Kr] 5s²

Electronic configuration of barium.

Ba = [Xe] 6s²

Electronic configuration of radium.

Ra = [ Rn] 7s²

They are present in group two and have same number of valance electrons (two valance electrons) and show oxidation state + 2 by loosing two valance electrons. They also show similar reactivity.

They react with oxygen and form oxide.

2Ba + O₂ → 2BaO

2Mg + O₂ → 2MgO

2Ca + O₂ → 2CaO

this oxide form hydroxide when react with water,

BaO + H₂O → Ba (OH) ₂

MgO + H₂O → Mg (OH) ₂

CaO + H₂O → Ca (OH) ₂

With sulfur,

Mg + S → MgS

Ca + S → CaS

Ba + S → BaS