How to Balance Redox Equations?

Chemistry help!! please! balance these ionic redox equations by any method....?

• Balance these ionic redox equations by any method A. Sb^3+ + MnO4^- --> SbO4^3- + Mn^2+ (in an acid solution) B. N2O + ClO^- --> Cl^- + NO2^- (in a basic solution) C. ClO3^- + SO2 --> Cl^- + SO4^2- (in an acid solution) please help me!

• Answer:

  The only method that I would recommend is the half-reaction method. Sb^3+ + MnO4^- --> SbO4^3- + Mn^2+ (in an acid solution) 5(Sb^3+ + 4H2O --> SbO4^3- + 8H+ + 2e-) 2(8H+ + MnO4^- + 5e- --> Mn2+ + 4H2O) ------------------------------- ------------------------------- 16H+ + 5Sb^3+ + 2MnO4^- + 20H2O --> 5SbO4^3- + 2Mn2+ + 8H2O + 40H+ simplify 5Sb^3+ + 2MnO4^- + 12H2O --> 5SbO4^3- + 2Mn2+ + 24H+ In acid solution, we balance oxygen with water, then then hydrogen with H+. In a basic solution, you balance oxygen with twice as many OH- as you need to balance the oxygen, and then balance the oxygen atoms and hydrogen atoms with H2O. N2O + ClO^- --> Cl^- + NO2^- (in a basic solution) N2O + 6OH- --> 2NO2^- + 3H2O + 4e- 2(H2O + ClO^- + 2e- --> Cl- + 2OH-) ------------------------- -------------------------- 2H2O + N2O + 2ClO- + 6OH- --> 2NO2^- + 2Cl- + 4OH- + 3H2O simplify N2O + 2ClO- + 2OH- --> 2NO2^- + 2Cl- + H2O