Question

Using half equations for the oxidation and reduction, develop the redox equation for the oxidation of cyclohexanone under acid conditions.

Answer 1

First of all lets review some terminology that will help us to understand better what is this all about

Oxidation: In organic chemistry, increasing the oxygen content of an organic molecule or decreasing its hydrogen content. Also creating a C-Z bond, where Z is an element that is more electronegative than C such as N, Halogen, etc. More generally, the process of removing electrons from a substance.

Reduction: In organic chemistry, increasing the hydrogen content of an organic molecule or decreasing its oxygen content. Also removing C-Z bonds. More generally, the process of adding electrons to a substance.

Oxidizing agent: A substance that causes an oxidation by accepting one or more electrons from a substrate. The oxidizing agent is reduced in the reaction.

Reducing agent: A substance that causes a reduction by donating one or more electrons to a substrate. The reducing agent is oxidized in the reaction.

The equation of the oxidation of cyclohexanone will be

2HCl + C₆H₁₀O + 2KMnO₄----> HOOC(CH₂)₄COOH + 2MnO₂ + 2KCl + Heat + H₂O

Half equations:

The first one is a redox equation. The cyclohexanone is oxidized to 1,6-hexanedioic acid (adipic acid) while the permanganate ion is reduced to MnO₂

C₆H₁₀O + 2KMnO₄ -----> 2MnO₂(s) + C₆H₈O₄K₂ + H₂O + heat.

The second equation describes the reaction which converts dipotassium adipate to adipic acid. Adipic acid is insoluble in water but the dipotassium salt is almost completely soluble in water; therefore the salt is converted to the acid.

C₆H₈O₄K₂ + 2HCl ----> C₆H₁₀O₄ + 2KCl.

Hope this woriks for you!