Q. For the four successive transition elements (Cr, Mn, Fe and Co), the stability of 2 oxidation state will be there in which of the following order?(At. nos. Cr = 24, Mn = 25, Fe = 26, Co = 27)

1. Cr > Mn > Co > Fe
2. Fe > Mn > Co > Cr
3. Mn > Fe > Cr > Co
4. Co > Mn > Fe > Cr