balance the following reactions by the redox half-reaction method H3PO3+NO3->PO43-+N2O4
The reaction is:
It occurs in acid medium.
Splitting it in two half-reactions, we get
The oxidation half-reaction: H3PO3 →PO4^3-+ 2e^-
The atom balanced oxidation half-reaction:
H3PO3 + H2O → PO4^3- + 5H^+ + 2e^-
And the atom balanced reduction half-reaction:
2NO3^- + 4H^+ 2e^- → N2O4 + 2H2O
Both these half-reactions are charge balanced already.
Adding these two half reactions,
H3PO3 + 2NO3^- + H2O + 4H^+ 2e^- → PO4^3- + N2O4 + 5H^+ + 2H2O + 2e^-
Cancelling equal terms from both sides, we get the balanced chemical equation for the reaction as:
H3PO3 + 2NO3^- → PO4^3- + N2O4 + H^+ + H2O