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The d & f Block Elements — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
How would you account for the following:
Cr2+ is reducing in nature while with the same d-orbital configuration (d4) Mn3+ is an oxidising agent.
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Answer

Cr2+ is reducing as its configuration changes from d4 to d3, a more stable half-filled t2g configuration while Mn3+ is oxidising as Mn3+ to Mn2+ change results in a more stable half-filled d5 configuration.

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