Question

Water is oxidized to oxygen by:
A.Ozone
B.${\text{KMn}}{{\text{O}}_{\text{4}}}$
C.${{\text{H}}_{\text{2}}}{{\text{O}}_{\text{2}}}$
D.${{\text{F}}_2}$
E.${\text{Cl}}{{\text{O}}_2}$

Answer 1

Water oxidation is the process of conversion of water into oxygen gas and protons. Since oxygen is a very strong oxidising agent, it can be oxidized only by an atom which is even more electronegative than oxygen atom itself.

Complete step by step answer:
Oxygen in water is present in $- 2$ oxidation state.
In option A, we have ozone.
In ozone, the oxidising agent is an oxygen atom. Thus it cannot oxidize water from its more stable $- 2$oxidation state to dioxygen with an oxidation state of oxygen as $0$.
Similarly, the other options, potassium permanganate $\left( {{\text{KMn}}{{\text{O}}_{\text{4}}}} \right)$, hydrogen peroxide $\left( {{{\text{H}}_{\text{2}}}{{\text{O}}_{\text{2}}}} \right)$ and chlorine dioxide $\left( {{\text{Cl}}{{\text{O}}_2}} \right)$ cannot oxidize water.
Fluorine is the most electronegative atom and also a stronger oxidizing agent than oxygen. Thus, water is oxidized by ${{\text{F}}_2}$ forming oxygen gas and protons. Fluorine is reduced to fluoride ion and water is oxidized from $- 2$ oxidation state to zero oxidation state.
When fluorine reacts with water, the reaction can be given as,
$2{{\text{F}}_2} + 2{{\text{H}}_2}{\text{O}} \to {\text{4}}{{\text{H}}^ + } + 4{{\text{F}}^ - } + {{\text{O}}_2} \uparrow$

Thus, the correct option is D.

Note:
The process of water oxidation might be confused with water oxidation often.
Water oxidation is the process in which water is oxidized to oxygen gas only and the other species involved in the reaction is reduced.The chemical conversion of water molecules into hydrogen gas and oxygen gas is known as water splitting. The water splitting reaction of salt water is generally used to make chlorine industrially. Water splitting can be achieved through various methods, namely photo catalysis, thermal decomposition, photoelectric splitting, radiolysis, and electrolysis of water