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By: Devin Laudenschlager
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In 1911, Rutherford and his coworkers at the
University of Manchester, decided to test what was
then the theory of atomic structure.
They used massive alpha particles.
Alpha Particles- helium atoms that lost two electrons.
double positive charge due to remaining protons.
The belief was that the Alpha particles would pass
easily though the gold with only slight deflection.
This was said to happen because of the positive charge
that spread out in gold atoms.
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The mast majority of alpha particles passed
through the gold atoms without deflection.
The small portion of alpha particles bounced
off the gold foil at very large angles.
Not many bounced back.
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Rutherford created a new theory based on his
results of the gold foil experiment.
His theory was the atom is empty space,
explaining the lack of deflection of most of the
alpha particles.
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All the positive charge and almost all the mass
are concentrated in a small region that has
enough positive charge.
This would cause greater deflection of the
alpha particles.
He called this region the nucleus.
Nucleus- Central core of atom.
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It is known as the nuclear atom
Nuclear Atom- The protons and neutrons are
located in the nucleus. The electrons are
distributed around the nucleus and occupy
almost all the volume of the atom.
Rutherford portrays the nucleus to be small
compared to the atom.
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