Question

write down the sequence of filling of electron in different subshell​

Answer 1

According to Aufbau principle, the subshell with minimum energy is filled up first and when this obtains maximum number of electrons, then the next subshell of higher energy starts filling. Sequence comes out to be : 1s, 2s, 2p, 3s,3p, 4s,3d, 4p, 5s, 4d, 5p, 6s, 4f, etc.