K₂Cr₂O₇ (potassium dichromate) is a strong:
AReductant
BReducing agent
CCatalyst
DOxidizing agent (Cr goes from +6 to +3)
Answer & Solution
Correct answer: D. Oxidizing agent (Cr goes from +6 to +3)
In acidic medium: Cr₂O₇²⁻ + 14 H⁺ + 6 e⁻ → 2 Cr³⁺ + 7 H₂O (E° = +1.33 V). Strong oxidizer. Orange-red color. Used in volumetric analysis and tanning. KMnO₄ even stronger oxidizer.
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