Question

Which of the following reaction does not involve either oxidation or reduction?

Options

• \[\ce{VO^{2+} -> V2O3}\]

• \[\ce{Na -> Na+}\]

• \[\ce{CrO^{2-}_4 -> Cr2O^{2-}_7}\]

• \[\ce{Zn^{2+} -> Zn}\]

Answer 1

\[\ce{CrO^{2-}_4 -> Cr2O^{2-}_7}\]

Explanation:

Cr remains in the same oxidation state +6.