Download Document

http://memekid.com/funny-pictures-about-going-back-to-school.htm
 Mass
 Energy
 Atomic Number
 Atomic Mass
 Atomic Charges
 Radioactivity
 Radioactive decay
 Half-life
 Ionizing-Radiation
 Alpha Decay
 Gamma Decay
 Beta Decay
 Excited State
 Ground State
 Isotope
 Fusion
 Fission
 Transmutation
 Nuclide
 Law of Conservation of Mass
 Law of Conservation of Energy
 Einstein’s E=MC2
How does a nuclear reactor work?
At nuclear power plants,
the heat to make the steam
is created when uranium
atoms split – called fission.
There is no combustion in a
nuclear reactor. Here's how
the process works.
Pressurized Water Reactors
(also known as PWRs) keep
water under pressure so
that it heats, but does not
boil.
http://www.lanl.gov/science/1663/images/reactor.jpg
How does a small mass contained
in this bomb cause……
• Nuclear
Bomb of
1945
known as
“fat man”
http://www.travisairmuseum.org/assets/images/fatman.jpg
…this huge nuclear explosion?
http://library.thinkquest.org/06aug/01200/Graphics/705px-Nuclear_fireball.jpg
Like this
• Starting nuclear chain reactions = releases a huge amount of energy (E)
• Per unit volume, an atom bomb may be millions or billions of times more
powerful than TNT.
• Nuclear reactions (rxn) occur: neutrons r fired @ closely packed atoms w/
heavy nuclei (uranium or plutonium isotopes).
• The heavy nuclei break apart into lighter nuclei (fission) when hit by
a neutron, then it generates more neutrons which bombard other
nuclei, creating a chain reaction.
• Breaking the nuclei rather than releasing E thru a regular chem rxn, atom
bombs can release more than 80 terajoules of E per kilogram (TJ/kg).
• Fusion releases E by fusing together nuclei rather than breaking them
apart.
Notation
Isotopes
• Atoms of a given element with:
same #protons
but
different # neutrons
H
H
H
http://education.jlab.org/glossary/isotope.html
Isotopes of Carbon
Radioactive Isotopes
• Isotopes of certain unstable elements that
spontaneously release (emit) particles and
E from the nucleus.
3 Main Types of Radioactive Decay
• Alpha
α
• Beta
β
• Gamma γ
Energy
Alpha Decay
Emission of alpha particles α :
• helium nuclei
• two protons and two neutrons
• can travel a few inches through air
• can be stopped by a sheet of paper,
clothing.
• Low E
Alpha Decay
Alpha
Particle
Uranium
Thorium
Beta Decay
• Beta particles β: e- ejected from the
nucleus when neutrons decay
• Beta particles have the same charge & mass as
e-.
• Can be stopped by aluminum foil or a block of
wood.
• Slightly higher E than alpha
Beta Decay
Beta
Particle
Thorium
Protactinium
Gamma Decay
• Gamma radiation γ : electromagnetic (EM)
E that is released.
• Gamma rays r (EM) waves.
• no mass/charge.
– Most Penetrating, can be stopped by 1m thick
concrete or a several cm thick sheet of lead.
• Ultra High E