Chromium has the electronic configuration 4s1 3d5rather than4s2, 3d4 because:
(1) 4s and 3d have the same energy
(2) 4s has a higher energy than 3d
(3)4s1 is more stable than 4s1
(4)4s1 3d5 half-filled is more stable than 4s2 3d4
Ans: 4s1 3d5 half-filled is more stable than 4s2 3d4