Question

Explain the term reduction reaction with an example involving the reaction of hydrogen sulphide with chlorine .

Answer 1

The term reduction can be defined in 3 ways :-

(i) Addition of hydrogen to an element or compound or the removal of oxygen from a compound.

(ii) Addition of electropositive element or removal of any other electronegative element.

(iii) The gain of electrons by an atom, ion or molecule.

For e.g. :- $H_2\stackrel{-2}{S}+{\stackrel{0}{Cl}}_2⟶2\stackrel{-1}{HCl}+\stackrel{0}{S}$

Here, ${Cl}_2$ is reduced as electron is gained by the chlorine atom to form ${Cl}^{-}$ ion which satisfies definition (iii) as mentioned above.