CaO + H2O -> Ca(OH)2 or Ca+ + 2OH-?

Based on solubility law, I think net ionic equation would be CaO(s) + H2O(l) -> Ca+(aq) + 2OH-(aq)

but some claim that since CaO is an weak base, it should be combined with OH, thus CaO(aq) + H2O(aq) -> Ca(OH)2(aq)

Which one is right and why?

Sol87:

The correct net ionic equation for the reaction between CaO and H2O depends on the conditions under which the reaction occurs.

If the reaction takes place in water and CaO is in solid form, then the net ionic equation is:

CaO(s) + H2O(l) -> Ca2+(aq) + 2OH-(aq)

This is because CaO is a strong base and will react with water to produce the Ca2+ and OH- ions. The Ca2+ ions will then combine with the OH- ions to form Ca(OH)2, which is a sparingly soluble compound.

On the other hand, if CaO is already in aqueous form (i.e., it has been dissolved in water), then the net ionic equation would be:

CaO(aq) + H2O(l) -> Ca(OH)2(aq)

This is because, in solution, CaO behaves as a weak base and will react with water to form Ca(OH)2, which is a more stable compound in water.

Therefore, both equations are technically correct, but the appropriate net ionic equation depends on the specific conditions of the reaction.