JEE MAIN - Chemistry (2003 - No. 55)
The number of d-electrons retained in Fe2+ (At no of Fe = 26) ion is :
4
5
6
3
Paliwanag
Fe (Z = 26) $$\to$$ e- = 26
Fe2+ (Z = 26) $$\to$$ e- = 24
Electronic configuration:
Fe (Z = 26) $$\to$$ 1s2 2s2 2p6 3s2 3p6 3d6 4s2
Fe2+ (Z = 26) $$\to$$ 1s2 2s2 2p6 3s2 3p6 3d6 4s0
as 4s is the outermost shell of Fe that's why e- will always removed first from 4s, so retained e- in d-shell is 6
Fe2+ (Z = 26) $$\to$$ e- = 24
Electronic configuration:
Fe (Z = 26) $$\to$$ 1s2 2s2 2p6 3s2 3p6 3d6 4s2
Fe2+ (Z = 26) $$\to$$ 1s2 2s2 2p6 3s2 3p6 3d6 4s0
as 4s is the outermost shell of Fe that's why e- will always removed first from 4s, so retained e- in d-shell is 6