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- How to get the valencies of elements? 3 answers
I'm trying to understand why ChemReference sometimes lists the valence electrons as a number I don't expect. Take Oxygen, for instance. It should have six valence electrons, however the site lists two. Why?
I hear that, for transition metals, the d-orbitals count towards the valence. Is there another rule like that I need to know about that might explain Oxygen?