Questions and Answers
What's the difference between hydrogen, nitrogen, oxygen, neon, copper, gold and magnesium?
The single most important difference between these elements is the number of protons each one contains in its nucleus. The number of protons an atom contains dictates how many electrons it will have. It is the arrangement of electrons around an atom's nucleus that determines that atom's chemical properties.
Steve Gagnon, Science Education Specialist (Other answers by Steve Gagnon)