| MadSci Network: Chemistry |
Atoms can have more than 8 electrons in their outer shell - as you show, Palladium has 18. I think you are referring to the octet rule which states that atoms are more stable when they have a total of 8 electrons in their outer energy level, shared in bonds or otherwise. This rule holds for atoms in the first two periods (and thus applies to most of organic chemistry), but does not hold for atoms in the 3rd period.
- L. Bry, MAD.SCI Admin
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