Question

Explain, by giving an example, how oxidation and reduction proceed side by side.

Answer 1

Oxidation and reduction always occur simultaneously. When one substance loses electrons (oxidation), another substance gains those electrons (reduction).

\[\ce{CuO + H2 -> Cu + H2O}\]

Copper oxide (CuO) loses oxygen and is converted to copper (Cu). Hence, CuO is reduced. Hydrogen (H₂) gains oxygen and is converted to water (H₂O). Hence, H₂ is oxidised.

Thus, oxidation and reduction proceed side by side in the same reaction; such reactions are called redox reactions.