Types of Nuclear Reactions
Video Notes
Nuclear Science
Natural transmutation
Artificial transmutation – bombardment
Particle accelerators are used to bombard the
atom to perform transmutation
Nuclear Science
Bombarding a nucleus with neutrons will
cause it to split
When the bullets are positively charged,
they are repelled by the nucleus they are
bombarding. To overcome the repulsions,
they must be accelerated to very high
speeds by particle accelerators.
Nuclear Science
Han and Strassman bombarded uranium
with neutrons and ended up with barium, an
element with ½ the mass of uranium.
This was the first fission reaction.
Nuclear Science
nuclear fission - Heavy nuclei are
bombarded with neutrons and split.
The mass of the products is less than
reactants. The difference comes from the
conversion of mass into energy.
Nuclear Science
Mass of particles produced is slightly more
than the mass of the reactants.
This mass is converted into energy.
(E = mc2)
Nuclear Science
Three neutrons are released when the
uranium atom is split, allowing for a chain
reaction to occur
Critical Mass
Minimum mass of fissionable material required
for a chain reaction
In nuclear reactors, fission is controlled
Nuclear Science
Fermi’s reactor
Graphite blocks separated the radioactive rods
and the control rods
The control rods can be removed to increase
the reaction or inserted to slow down the
reaction
Modern reactors
Use the same principle as Fermi’s, but use
water instead of the graphite
Nuclear Science
Manhattan project
Secret project to build nuclear bombs from
uranium and plutonium
Headed by Dr. Robert Oppenheimer
Test bomb was exploded at Trinity site in the
New Mexico desert
The Nuclear Age had begun
Nuclear Science
Fusion is combination of two nuclei into one with
release of energy
Mass of particles produced is much less than the
mass of source
Fusion reactions can only be created by the very
high temperatures only found in a fission reaction