Oxidation and Reduction Reactions is abbreviated as redox reaction.
(i) Oxidation is the addition of oxygen but the removal of hydrogen. Reduction is the removal of oxygen
(ii) In terms of electron transfer – Reduction Is the gaining of electron(s) while oxidation is the loss of electron(s).
Na+ + e– → Na(s) Reduction
2CL– – 2e– → CL2(g) Oxidation
(iii) In terms of oxidation number oxidation is increased in oxidation number while reduction is decreased In oxidation number.
(iv) In terms of electronegativity and electropositivity. Oxidation is addition of electronegativity but removal of electropositivity while reduction is addition of electropositivity but loss of electronegativity.
NB: In redox reaction, oxidizing agents are reduced while reducing agents are oxidized.