Question

H3PO2 is a stronger reducing agent than H3PO3. Why?

Answer 1

There is no P-H bond...it may be related to the bond strengths of P-O (which differ the O-H bond energies) in each compound..

Answer 2

Hey !!

In H₃PO₂, oxidation state of P is +1 which can be further oxidized to a higher oxidation state. While in H₃PO₄, oxidation state of P is +5, which is highest for P. It cannot be further oxidized. Hence, H₃PO₄ is a weaker reducing agent.

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