# What is the correct net ionic equation for the neutralization of phosphoric acid? [duplicate]

What is the net ionic equation for the reaction between phosphoric acid and sodium hydroxide?

I came up with
\begin{align} \tag1 \ce{H+ + H2PO4- + OH- &-> PO4^3- + H2O},\\ \tag2 \ce{H+ + OH- &-> H2O}. \end{align}

Or is it, since phosphoric acid is a triprotic acid, whose ionization is $$\ce{H3PO4 <=>3H+ + PO4^3-},$$ therefore the net ionic equation will be $$\ce{3H+ + 3OH- -> 3H2O}?$$

## marked as duplicate by Klaus-Dieter Warzecha, Geoff Hutchison, Freddy, ron, PhilippSep 22 '14 at 18:04

Phosphoric acid dissociates into hydrogen ions and $$\ce{H2PO4^-}$$ ions in water. This then can dissociate further, but $$\ce{H^+}$$ and $$\ce{H2PO4^-}$$ are the primary ionic species you'd find in a phosphoric acid solution.
$$\ce{NaOH}$$ dissociates completely into $$\ce{Na^+}$$ and $$\ce{OH^-}$$ ions.
The reaction would then be between $$\ce{H^+}$$ and $$\ce{OH^-}$$, your option 2.
The difficulty arises because adding more $$\ce{NaOH}$$ to the reaction pulls off the second then the third hydrogen from the phosphoric acid. In all cases it is an $$\ce{H^+}$$ reacting with an $$\ce{OH^-}$$ ion with the phosphate ions as spectators, but that really doesn't tell the story of the reaction well. This is a case where the net ionic equation really isn't your best option.emphasized text