Question

Balance the redox reaction equation (occurring in acidic solution) and choose the correct coefficients for each reactant and product.__pbo2(s)+__sn(s)+__h+(aq)→__pb2+(aq)+__sn2+(aq)+__h2o(l)

Answer 1

Balanced chemical reaction: 
PbO₂(s) + Sn(s)+ 4H⁺(aq) → Pb²⁺(aq) + Sn²⁺(aq) + 2H₂O(l).
Oxidation half-reaction: Sn → Sn²⁺ + 2e⁻.
Reduction half-reaction: PbO₂ + 4H⁺ + 2e⁻ → Pb²⁺ + 2H₂O.
Net reaction: Sn + PbO₂ + 4H⁺ + 2e⁻ → Sn²⁺ + 2e⁻ + Pb²⁺ + 2H₂O.
Oxidation is increase of oxidation number, reduction is decrease of oxidation number.