(a) Hydrogenation reaction

(b) Oxidation reaction

(c) Substitution reaction

(d) Saponification reaction

(e) Combustion reaction

Answers:

(a) Hydrogenation reaction – The addition reaction between the hydrogen and other compounds with the catalyst presence.

Reaction Involved:

CH₂ = CH₂ → CH₃CH₃

(b) Oxidation reaction – Oxygen joins with an element or a compound (or) the loss of electron in a molecule.

Reaction Involved:

2Mg + O₂→ 2MgO

(c) Substitution reaction – From a aqueous salt solution, high reactive element displaces a low reactive element.

Reaction Involved:

Zn + CuSO4 → ZnSO4 + Cu

(d) Saponification reaction – Hydrolysis of an ester in the presence of NaOH or KOH.

Reaction Involved:

CH₃COOC₂H₅ + NaOH → C₂H₅OH + CH₃COONa

(e) Combustion reaction – Oxygen joins with a compound to form CO2 and H2O.

Reaction Involved:

CH₄ + 2O₂ → 2H₂O + CO₂