Is it essential that oxidation and reduction must occur side by side in a chemical reaction ? Explain.

Explanation

In a chemical reaction, if oxidation takes place then subsequently reduction also take place because electrons that are lost during oxidation are at the same time gained during reduction and vice versa.
Let us take an example, When zinc reacts with copper sulphate solution to form zinc sulphate and copper.
`CuSO_4 + Zn to ZnSO_4 + Cu`
`Cu^(2+) SO_4^(2-) + Zn to Zn^(2+) SO_4^(2-)+Cu`
Writing Half reaction
`Zn to Zn^(2+) + 2e^(-)` (oxidation)
`Cu^(2+) + 2e^(-) to Cu` (reduction)
They occurs simultaneously as

Thus , oxidation and reduction always go side by side.