Resources

Periodic Table of Oxidation States - Compound Chem has a wonderful array of infographics. The most useful to our lab is this periodic table with all possible and preferred oxidation states.

PTable - PTable.com is the best interactive periodic table on the web hands down.

EuChemS Element Scarcity - The European Chemical Society frequently updates this periodic table that shows both how common elements are and how sustainable, or not, our usage is.