With respect to acidity, how does H_3PO_4 behave in aqueous solution?

Jul 1, 2017

Well, phosphoric acid is a fairly WEAK acid.......but in aqueous solution it is a diacid.........

Explanation:

${H}_{3} P {O}_{4} \left(a q\right) + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s {H}_{2} P {O}_{4}^{-} + {H}_{3} {O}^{+}$

${H}_{2} P {O}_{4}^{2 -}$ does undergo some dissociation in aqueous solution.......

${H}_{2} P {O}_{4}^{-} \left(a q\right) + {H}_{2} O \left(l\right) r i g h t \le f t h a r p \infty n s H P {O}_{4}^{2 -} + {H}_{3} {O}^{+}$

The third dissociation is largely irrelevant and non-operative in aqueous solution........You will have to look up $p {K}_{a 1}$, $p {K}_{a 2}$ yisself.