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Determine how many of the following reactions involve NO redox change: (I) BaCl2 + Na2CrO4 (in CH3COOH) (II) K2Cr2O7 + NaOH (III) Cr2O7²- + NO3- (in H+) (IV) Cr2O7²- + C2H5OH (in H+)
- 1
- 2
- 3
- 4
Correct answer: 2
Solution
Reactions (I) precipitation of BaCrO4 and (II) dichromate-chromate interconversion involve no oxidation-state change; (III) and (IV) reduce Cr(VI) so they are redox.
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