What may be the stable oxidation state of the transition element with the following d electron configurations in the ground state of their atoms : `3d^(3),3d^(5),3d^(8)`and `3d^(4)`?

Explanation

`3d^(3) 4s^(2) = + 5 , 3d^(5) 4s^(1) = + 6 , 3d^(5) 4s^(2) = +2 , + 7 , 3d^(8) 4s^(2) = + 2 , 3d^(4) 4s^*(2) = 3d^(5) 4s^(1) = + 6 ( & + 3)`
Note. The maximum oxidation states of reasonable stability correspond to the sum of s and d- electrons upton Mn. After that, there is abrupt decrease in the stability of higher oxidation states.