In the reaction,Cr2O72- + 14 H+-> 2 Cr3++7H2OHow many electrons are gained or lost by chromium atom?
Correct answer: B. +3 e-
- A. +12 e
- B. +3 e-
- C. +6 e
- D. -6 e-
Explanation
In this reaction, each Cr atom goes from a +6 oxidation state (in Cr2O72-) to a +3 oxidation state (in Cr3+). So, each atom get 3 electrons.
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