text: In acidic medium, H ions and water are added to balance each half-reaction.
  For example, when manganese reacts with sodium bismuthate.
  :Unbalanced reaction: Mn + NaBiO → Bi + 
  :Oxidation: 4 HO + Mn →  + 8 H + 5 e
  :Reduction: 2 e + 6 H +  → Bi + 3 HO
  Finally, the reaction is balanced by multiplying the stoichiometric coefficients so the numbers of electrons in both half reactions match
  :8 HO + 2 Mn → 2  + 16 H + 10 e
  :10 e + 30 H + 5  → 5 Bi + 15 HO
  and adding the resulting half reactions to give the balanced reaction:
  :14 H + 2 Mn + 5 NaBiO → 7 HO + 2  + 5 Bi + 5 Na