Download Fission & Fusion PPT

Drill – 10/25
1. Write the nuclear equation for the alpha
decay of Pu-239
2. Write the nuclear equation for the
electron capture of Argon-37.
Test on Thursday – 10/28
From Chapter 3:
–
–
–
–
–
Atomic number, Average Atomic Mass, Mass #
Protons, neutrons, electrons
Ions & Isotopes
Calculating average atomic mass
Atomic Structure History (know famous
scientists/experiments/atomic models)
– Mole, Molar mass, & Avogadro’s number
– Converting between moles, mass, & particles
From Chapter 21:
– Balancing nuclear reactions
– Types of radioactive decay (alpha, beta, gamma, positron,
electron capture)
– Why radioactive decay occurs
– Half-life
– Fusion & Fission
Nuclear Fission and Fusion
Radiation
Alpha
Beta
Gamma
Composition
& Symbol
Is shielded or
stopped by?
Shielding Radiation
, aluminum
• Alpha & beta do not cause internal harm to
humans
• Gamma radiation harms living cells. It is
used to clean medical equipment and
irradiation of bacteria from foods.
• Gamma radiation can break DNA strands
and cause mutations (ex. in the gene to
suppress tumor production and the gene
to repair DNA), causing cancer.
• Gamma radiation can also treat cancer by
killing cancer cells. The radiation is
directed at cancer cells and kills them first
because they are replicating the fastest.
Nuclear Fission
• A heavy nucleus splits into more stable
nuclei of intermediate mass.
A-bombs
• Atomic bombs are an
example of Fission
Reactions.
• “Little boy” and “Fat man”
were Atomic bombs made
from fission reactions with
uranium and plutonium
respectively.
• A fission chain reaction is
started and continues until
the bomb destroys itself.
Nuclear Power Plants
map: Nuclear Energy Institute
Nuclear Power Plants
• Uranium-235 undergoes nuclear fission
and releases thermal (heat) energy.
• This turns water to steam which spins
turbines.
• The turbines produce electrical energy.
• Nuclear waste is fuel rods with unreacted
uranium and radioactive products of
fission. Right now this waste is buried in
waste management facilities, like Yucca
Mountain.
Nuclear Fusion
• Low-mass nuclei combine to form a
heavier, more stable nucleus.
Requires high
temperatures
and/or pressure
and often a
fission reaction
to get the initial
particles.
Hydrogen Bombs
• Hydrogen bombs are an example of
nuclear fusion.
• Two isotopes of hydrogen, 2H and 3H, fuse
together to produce a lot of energy in the
process.
• H-bombs release significantly more energy
than atomic bombs.
The Sun: Nuclear
Fusion
Sun
+
+
1
41 H
Four
hydrogen
nuclei
(protons)

0
2-1 e
Two beta
particles
(electrons)
4
2
He +
One
helium
nucleus
Energy
Nuclear Fission
Nuclear Fusion
Nuclear Fission
A heavy atom
splits into two
or more lighter
nuclei
Ex: Atomic
Bombs &
Nuclear
reactors
Nuclear Fusion
Release
huge
amounts of
energy
Produce
nuclear
waste
High temp and
pressure are
used to
combine light
atoms to make
heavier atoms
Ex: Fuels the
sun and stars
& Hydrogen
Bombs