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Q145) The correct electron configuration for Ni2+ is (Z=28)


Ni2+ have electrons=28-2=26
Aragon Ar have 18 electron thus electron in outer orbit=26-18=8 last orbit for Ar is 3p , actually 2 electrons should go to 4s but energy of 4s and 3d is similar, quantum number of 3d is smaller than 4s thus electrons goes in orbit of 3d
Note while filling electrons it will follow abf-bau rule, above explanation is valid only for removal of electrons
Answer: (c)