Transmutation, nuclear reactors, fission v. fusion

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Transmutation
(Objective 25.6: Identify two ways transmutation can occur)
 Transmutation is the conversion of an atom of one
element to the atom of another element
 Happens naturally during radioactive decay

Examples?
 Happens when particles (usually alpha particles,
protons or neutrons) bombard the nucleus of an
atom

Examples: every element above atomic #92 was made
artificially in the laboratory
Man-made elements
 Example: creating plutonium-239 from uranium-
238
Practicing Transmutation
 Write an equation for the transmutation of
protactinium-232 by bombardment with a neutron.
One of the 2 products is a beta particle.
 Write an equation for the transmutation of
beryllium-9 with an alpha particle. One of the two
products is a neutron.
Fission v. Fusion
Objective 25.9: Distinguish fission reactions from fusion reactions.
 Fission- splitting of nucleus
into smaller fragments



Only two isotopes that are
fissionable: uranium-235 and
plutonium-239
Releases a lot of energy
Also releases neutrons– creates a
chain reaction- these neutrons
react with other fissionable nuclei
which release more neutrons…..
Uses of Fission: Nuclear Power Plant
Objective25.8: Explain how a nuclear power plant works.
Uses of Fission: Nuclear Power Plant
Objective25.8: Explain how a nuclear power plant works.
 Nuclear energy  heat energy  mechanical energy
 electrical energy
 Neutron moderators


used to increase energy release by slowing down neutrons so
that they actually cause fission
Rods of carbon or water
 Neutron absorbers
 Used to decrease energy release by decreasing the number of
moving neutrons
 Rods of cadmium
Nuclear Waste
Fusion
 Fusion- when nuclei combine to produce a nucleus of
greater mass

Example
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