🎁Question 1- which of the 3d series of transition metal exhibit the lowest oxidation state? (Chemistry 2017-18 AMU +2)

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Which transition element of the 3d series   exhibit the largest number of oxidation states and why?

Manganese exhibit the largest number of oxidation states. It shows the oxidation states +2, +3, +4, +5 ,+6,  and + 7.The reason for that is the maximum number of unpaired electrons present in its outermost shell i.e. 3d⁵4s².