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Q & A: atomic shells

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Most recent answer: 10/22/2007
Q:
In an atom, what is the "shell" that holds the electrons?
- Emily (age 13)
Riverview Middle School, Plymouth, WI
A:
Nice question! There really is no ’shell’ or anything like that sitting around waiting for electrons to fall in. The electrons are actually wave-like objects. The atom can support only certain frequencies of these waves, just like a musical instrument will only vibrate at certain frequencies. It turns out that the frequency in quantum mechanics is what we call energy. The ’shells’ are just collections of certain possible wave-states for the electrons with definite energies. But there’s nothing there except the electrons and the atom nucleus.

Mike W.

(published on 10/22/2007)

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