Question

2. [Ar]3d4s
A. Expand the above electronic configuration.
B. The element that comes just before the above one
has 4s configurations, but the given element has
only 4s! Give the reason.​

Answer 1

Answer:

A.1s^2 2s^2 2p^6 3s^2 3p^6 3d^3 4s^2 and element will be vanadium

B. it will be chromium becz it's atomic no. was 24 (Ar)3d^5 4s^1 to gain stability .