A Question About Selection Rules

[CollectiveRocker]

A hydrogen atom is in the 4p state. To what state or states can it go by radiating a photon in an allowed transition? Anyone have any ideas?

[Leo32]

The hydrogen atom as such is not in a state of any kind, the electron swirling around the proton does.

In order to start thinking about the solution, ask yourself what happens to this energy state when a photon is radiated. Is it higher or lower ?

Regards,
Leo

[CollectiveRocker]

So can it only go to a 4s state or 4d state, because of the rule which says: allowed transitions are: ∆l = +- l?