Question

Which of the following undergo disproportionation in water?
1) F2
2) Cl2
3) Br2
4) I2

Answer 1

In a disproportionation reaction, the reactant takes part in redox reaxtion (both oxidation and reduction occurs simultaneously).

Cl₂ undergoes disproportionation in water, the reaction is-

Cl₂ + H₂O → HCl + HClO

Valency of Cl₂ (elemental state) = 0

Valency of Cl in HCl = -1

So, Cl is reduced to Cl⁻ in HCl.

Valency of Cl in HClO = +1

Here, Cl is oxidised to HClO.

Since, fluorine is the strongest oxidising agent so, it does not have any positive oxidation state. Hence, F₂ does not undergo disproportionation in water.

Similarly, Br₂ and I₂ does not undergo disproportionation in water.

Answer 2

Answer:

Explanation:

In a disproportionation reaction, the reactant takes part in redox reaxtion (both oxidation and reduction occurs simultaneously).

Cl₂ undergoes disproportionation in water, the reaction is-

Cl₂ + H₂O → HCl + HClO

Valency of Cl₂ (elemental state) = 0

Valency of Cl in HCl = -1

So, Cl is reduced to Cl⁻ in HCl.

Valency of Cl in HClO = +1

Here, Cl is oxidised to HClO.