Question

How do you write the ionization equation for calcium hydroxide: Ca(OH)2?

This is a base that would ionize completely, and the dissociation equation would look like this: Ca(OH)2 <----> Ca2+ 2OH- , but how would I write the Bronsted equation with water? Ca(OH)2 + H2O --> ?

I know that water auto-ionizes to make H3O+ and OH-.

Answer 1

`Ca(OH)_2(s) -> Ca^2+(aq) + OH^-(aq)`

Explanation:

There is no need to include water in the ionization equation, you just need to include the states in your equation:

`Ca(OH)_2(s) -> Ca^(2+)(aq) + OH^(-)(aq)`

You may want to write an equation corresponding to the hydroxide displacement in water (The Grotthuss mechanism) but it is not a measurable process since the reactants and products are the same.

`OH^(-) + H_2O -> OH_2 + HO^-`