Question

Which of the following reaction is an example of a redox reaction?

• A. ${\mathrm{XeF}}_6+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeOF}}_4+2\mathrm{HF}$
• B. ${\mathrm{XeF}}_4+{\mathrm{O}}_2{\mathrm{F}}_2\to {\mathrm{XeF}}_6+{\mathrm{O}}_2$
• C. ${\mathrm{XeF}}_2+{\mathrm{PF}}_5\to {\left[\mathrm{XeF}\right]}^{+}+{{\mathrm{PF}}_6}^{-}$
• D. ${\mathrm{XeF}}_6+2{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeO}}_2{\mathrm{F}}_2+4\mathrm{HF}$

Answer 1

The correct option is B

${\mathrm{XeF}}_4+{\mathrm{O}}_2{\mathrm{F}}_2\to {\mathrm{XeF}}_6+{\mathrm{O}}_2$

The explanation for the correct option:

(B) ${\mathrm{XeF}}_4+{\mathrm{O}}_2{\mathrm{F}}_2\to {\mathrm{XeF}}_6+{\mathrm{O}}_2$

• This is a redox reaction since Xenon($\mathrm{Xe}$) is undergoing oxidation and Oxygen(${\mathrm{O}}_2$) is undergoing reduction.
• The oxidation number of Xenon changes from $+4$ to $+6$ due to the loss of electrons and the oxidation number of Oxygen changes from $+1$ to $0$ due to the gain of electrons.
• Hence, this is a redox reaction.

Hence, option B is correct.

The explanation for the incorrect option:

(A) ${\mathrm{XeF}}_6+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeOF}}_4+2\mathrm{HF}$

• The oxidation state of the Xenon species remains as $+6$ and the oxidation state of Oxygen remains as $-2$.
• There is no change in the oxidation state of Xenon or Oxygen and neither of the species is undergoing oxidation or reduction.
• Hence, this is not a redox reaction.

(C) ${\mathrm{XeF}}_2+{\mathrm{PF}}_5\to {\left[\mathrm{XeF}\right]}^{+}+{{\mathrm{PF}}_6}^{-}$

• The oxidation state of the Xenon species remains as $+2$ and the oxidation state of Phosphorous($\mathrm{P}$) remains as $+5$.
• There is no change in the oxidation state of Xenon or Phosphorous and neither of the species is undergoing oxidation or reduction.
• Hence, this is not a redox reaction.

(D) ${\mathrm{XeF}}_6+2{\mathrm{H}}_2\mathrm{O}\to {\mathrm{XeO}}_2{\mathrm{F}}_2+4\mathrm{HF}$

• The oxidation state of the Xenon species remains as $+6$ and the oxidation state of Oxygen remains as $-2$.
• There is no change in oxidation state of Xenon or Oxygen and neither of the species are undergoing oxidation or reduction.
• Hence, this is not a redox reaction.

Therefore, the correct option is (B) ${\mathrm{XeF}}_4+{\mathrm{O}}_2{\mathrm{F}}_2\to {\mathrm{XeF}}_6+{\mathrm{O}}_2$