Give the 4 quantum numbers for the highest energy electron in the valence shell of Osmium.

2 answers

Look up the electron configuration of Os; i.e., 1s2 2s2 2p6 3s2 3p6 3d10 .......That will give you the n value and the l value. With those you can finish. If you need further help, post what you can do and I can help you finish.
I looked up the electron configuration. It is Xe 4f14 5d6 6s2
The valence shell is the 6s2. Can you take it from here?