The electronic configuraiton of valence shell of Cu is `3d^10 4s^1` not `3d^9 4s^2`. How is this configuration explained?

Anomalous electronic configuration in the 3d series are of

The electronic configuration of Cu (II) is 3d^9 whereas that of Cu (I) is 3d^10 . Which of the following is correct?

Name the element with electronic configuration 1s2 2s1

Name the element with electronic configuration 1s2 2s2

Name the element with electronic configuration 1s2

Name the element with electronic configuration 1s2 2s2 2p6 3s1

General electronic configuration of actionoids is [Rn] 5f^(1-14) 6d^(0-1) 7s^2 . Which of the following actionoids have one electron in 6d orbital ?

Name the element with electronic configuration 1s2 2s2 2p6