df-Block

The number of d ­electrons retained in Fe2+ (At. no. Fe = 26) ions is

  1. 3
  2. 4
  3. 5
  4. 6

Answer

26Fe = 1s2 2s2 2p6 3s2 3p6 3d6 4s2

Fe++ = 1s2 2s2 2p6 3s2 3p6 3d6

The number of d ­electrons retained in Fe2+ = 6

The correct option is D.