Question

Distinguish between oxidation and reduction.

Answer 1

Oxidation	Reduction
According to the classical concept, oxidation is a process of the addition of oxygen or removal of hydrogen.	Reduction is a process of removal of oxygen or the addition of hydrogen.
Removal of hydrogen \[\ce{2H2S + O2 -> H2O + 2S}\]	Removal of oxygen \[\ce{ZnO + C -> Zn + CO}\]
Addition of oxygen \[\ce{C + O2 -> CO2}\]	Addition of hydrogen \[\ce{Ca + H2 -> CaH2}\]
According to the electronic concept, the loss of electrons is called an oxidation reaction. \[\ce{Ca -> Ca^2+ + 2e^-}\]	According to the electronic concept, the gain of electrons is called a reduction reaction. \[\ce{Zn^2+ + 2e^- -> Zn}\]
During oxidation, the oxidation number increases.	During reduction, oxidation number decreases.
During oxidation, the reducing agent gets oxidised.	During reduction, the oxidising agent gets reduced.