How to Balance Redox Equations in Alkaline (and Acid) Solutions?
The Fuel Cell of Hydrogen and Oxygen can take place in Acid or Alkaline Solution. H₂ + 2 O₂ ------> 2 H₂O In either situation we first balance the redox equations in acid solution Oxidation Half Equation H₂ -----> H₂O 1. Add H₂O to balance O H₂O + H₂ -----> H₂O 2. Balance H with H+ H₂O + H₂ -----> H₂O + 2H⁺ 3. Balance charge with e⁻ There is 0 on LHS and +2 on RHS so add 2e to the RHS H₂O + H₂ ----> H₂O + 2H⁺ + 2e⁻ Cancel H₂O The oxidation equation is balanced in acid solu
How to Balance Redox Equations
Sulphuric Acid is reduced by Iodide ions to form Sulphur Dioxide and Iodine. Reduction Half Equation H₂SO₄ -----> SO₂ 1. Balance the species that has been oxidised or reduced. In this case the sulphur has been reduced from +6 to +4. The sulphur atoms are balanced. 2. Balance oxygen using H₂O There are 4 on LHS and 2 on RHS so add 2 H20 to the RHS H₂SO₄ ----> SO₂ + 2H₂O 3. Balance hydrogen atoms (H+) There are 2 on LHS and 4 on RHS so add 2H+ to LHS H₂SO₄ + 2H⁺ ----> S
