Question

Write a net ionic equation for the overall reaction that occurs when aqueous solutions of phosphoric acid (h3po4) and potassium hydroxide are combined.assume excess base. use the pull-down boxes to specify states such as (aq) or (s).

Answer 1

Firstly, we have to show molecular equation (all compounds are showed as neutral molecules) for the reaction:

H₃PO₄(aq) + 3KOH(aq)  ⇒ K₃PO₄(aq) + 3H₂O(l) 

Then, the reaction has to be written as an ionic equation:

3H⁺(aq) + PO₄³⁻(aq) + 3K⁺(aq)+ 3OH⁻(aq) +   ⇒  3K⁺(aq) + PO₄³⁻(aq)  + 3H₂O(l) 

The molecule of water does not dissociate and it is shown as a molecule. Soluble ionic compounds H₃PO₄ and KOH are shown as dissociated ions.
Since there are not spectator ions (ions that do not participate in the reaction) the equation is at the same time and net ionic equation (ions and molecules involved in the reaction).