1. Zr (atomic number 40) : [Kr] 5s^2 4d^2 (1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^2) 2. Ti (atomic number 22) : [Ar] 4s^2 3d^2 (1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2) 3. Ce (atomic number 58): [Xe] 6s^2 4f^1 5d^1 (1s^2 2s^2 2p^6 3s^2 3p^6 4... read more