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Question
Which is a stronger reducing agent, Cr2+ or Fe2+ and why?
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Solution
Cr2+ is a stronger reducing agent than Fe2+. In the formation of Cr2+ to Cr3+, the change is d4 to d3, but in the formation of Fe2+ to Fe3+, the change is d6 to d5. In a medium like water, d3 is more stable than d5.
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