All combustion reactions are oxidation reaction but all oxidation reaction are not combustion reactions justify with examples

Dear student,
Yes, all combustion reactions are oxidation reactions because in a combustion reaction heat is always evolved. Since evolution of heat requires liberation of oxygen it is an oxidation reaction.Ex. CH₄ + 2O₂         > CO₂ + 2H₂O

But all oxidation reactions are not necessarily combustion reactions because in oxidation ractions it is not necessary that heat should be evolved.Ex. 2H₂+ O₂       > 2H₂O
Regards