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

1 Answer
Jul 1, 2017

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

Explanation:

#H_3PO_4(aq) + H_2O(l) rightleftharpoons H_2PO_4^(-) + H_3O^+#

#H_2PO_4^(2-)# does undergo some dissociation in aqueous solution.......

#H_2PO_4^(-)(aq) + H_2O(l) rightleftharpoons HPO_4^(2-) + H_3O^+#

The third dissociation is largely irrelevant and non-operative in aqueous solution........You will have to look up #pK_(a1)#, #pK_(a2)# yisself.

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