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

i) `3d^(3)` -stable oxidation states are +2, +3, +4 and +5 (V)
ii) `3d^(5)` -stable oxidation states are +3, +4 and +6 (Cr)
iii) `3d^(5)` -stable oxidation states are +2, +4, +6 and +7 (Mn)
iv) `3d^(8)` -stable oxidation states are +2, +3
v) `3d^(4)` -This configuration does not exist.