Question

In which orbital will electron enter first 3d or 4p

Answer 1

3d

Step-by-step explanation:

As according to afbau principle electron will first fill 3d then after that it fills in 4p orbital

Answer 2

Aufbau principle

1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 4f 5d 6p 7s 5f 6d 7p

So, it will enter 3d first.