I have a question regarding the possible oxidation states of metals. I understand how to find the oxidation state of a metal in a compound, that's pretty straightforward. What I'm interested in is finding possible oxidation states given only the name of the metal. For example, Cu has possible +1 and +2, how do I figure this out without looking it up? Or is it a purely experimental value? I don't really need to know for any particular reason, just so I don't have to look up possible values when I'm doing problems in the future. I would imagine it comes from the electron configuration, but I can't see any obvious correlation. Am I on the right track? Does anyone have any links on this? Thanks in advance for the help.