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प्रश्न
Which of the 3d series of the transition metals exhibits the largest number of oxidation states and why?
उत्तर
Mn (Z = 25) = 3d5 4s2
Mn has the maximum number of unpaired electrons present in the d-subshell (5 electrons). Hence, Mn exhibits the largest number of oxidation states, ranging from +2 to +7.
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