Group 2 hydroxides

• Going down the group, the solutions formed from the reaction of Group 2 oxides with water become more?alkaline
• When the oxides are dissolved in water, the following ionic reaction takes place:

O^2-?(aq) + H₂O(l) → 2OH^-?(aq)

• The higher the?concentration?of OH-?ions formed, the more?alkaline?the solution
• The?alkalinity?of the formed solution can therefore be explained by the?solubility?of the Group 2?hydroxides

Solubility of the Group 2 hydroxides table

• The hydroxides dissolve in water as follows:

X(OH)₂?(aq) → X(aq) + 2OH^-?(aq)

Where X is the Group 2 element

• When the metal oxides react with water, a Group 2 hydroxide is formed
• Going down the group, the?solubility?of these hydroxides?increases
• This means that the?concentration?of OH^-?ions?increases,?increasing the pH of the solution
• As a result, going down the group, the?alkalinity?of the solution formed increases when Group 2 oxides react with water

Going down the group, the solubility of the hydroxides increases which means that the solutions formed from the reactions of the Group 2 metal oxides and water become more alkaline going down the group

Group 2 sulfates

• The solubility of the Group 2 sulfates decreasing going down the group

Going down the group, the solubility of the sulfates decreases