Which reaction does not involve either oxidation or reduction?
Correct answer: C. CrO₄²⁻ → Cr₂O₇²⁻
- A. VO²⁺ → V₂O₃
- B. Na → Na⁺
- C. CrO₄²⁻ → Cr₂O₇²⁻
- D. Zn²⁺ → Zn
Explanation
In both the chromate (CrO₄²⁻) and dichromate (Cr₂O₇²⁻) ions, the oxidation state of chromium is +6. This reaction is a condensation reaction, not a redox reaction, as no element changes its oxidation state.
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