Given the reaction:

Question

Determine the oxidizing agent.
cn^-+ mno4^- → cno^- + mno2

Answer 1

Oxidizing agent is the one that is reduced.
Reduction is the gain of electrons.
MnO4^- + 8H^+ + 5e ==> Mn^2+ + 4H2O
CN^- + H2O ---> CNO^- + 2e + 2H^+
Which half equation gained electrons? That is the one that is reduced (and is the oxidizing agent)