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Re: radioactivity

Leigh Palmer wrote:

It's pretty straightforward. Neutrons are fermions and as such
two neutrons cannot occupy the same quantum mechanical state
in a nucleus. When all of the energetically bound quantum
states in a nucleus are occupied by neutrons, the next neutron
in must go into a higher (and therefor unbound) energy state.
Of course it will come right out, there being no barrier high
enough to hold it in.

The same mechanism operates in building up the electron shells
around the nucleus of an atom. There is a shell model of the
nucleus as well, largely due to Maria Goepert Mayer. That is
the model in which this explanation is most intuitively seen
to operate.

I'll add one more thing. It turns out that in the case of the
hydrogen atom in its ground state, it is possible to add one
more bound electron. The resulting object, the H- ion, is the
species principally responsible for the opacity of the Sun.

Does that help?

Leigh


Yes it does. Not a lot but it helps. What exactly do you mean
by
enegerticly bound quantum states? I do understand that there are
various
energy states within the nucleus as there are various states with

electrons. What would cause a neutron to be ejected at any time
regardless of the energy state it was found within? It certainly
would
not be electromagnetic force or gravitation or strong force. At
least
not the way I see things at this moment. I teach Chemistry I in
high
school and therefore we discuss Pauli exclusion principle in
terms of
electrons. At least as far as I have been able to understand it
myself
this has been a "because that's the way it is" sort of thing.
Perhaps
that's as far as it goes.

Line spectrum emissions give evidence to the quantum nature of
energy
relating to electrons. What is the evidence that lead to an
understanding of the quantum nature of energy relating to protons
and
neutrons?

--
Cliff Parker

Never express yourself more clearly than you can think. --
Niels Bohr