Which is a conjugate pair in the following equilibrium?

Question

H2C2O4(aq) + HPO4(aq) 2- HC2O4(aq)- + H2PO4(aq)-

Answer 1

The acid has more H, the base has less fewer H.
For example, H2C2O4 is the acid; HC2O4^- is the base.

Answer 2

HPO4 2- and H2PO4 - is a conj pair
H2C2O4 and HC2O4 is a conj jpair

Answer 3

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