The Power of the Atom
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Transcript of The Power of the Atom
The Power of the
Atom
Visualizing the Energy
Releasing stored energy
What is your stand on the
issue?
PROS AND CONS
List below the Pros and Cons of nuclear power in our society.
PROS CONS
Group position: Is harnessing the “Power of the Atom” the solution to our environmental crisis? Is it worth the risk?
Facilitator Time Keeper Recorder
April 26, 1986
http://library.thinkquest.org/3426/data/introduction/index.html
Nov 21, 2004- Chernobyl Disaster ( Cesium-137) Caused Cancer Cases In Sweden
Chernobyl linked to cancer in Europe21 November 2004 08:44
Scientific evidence has emerged for the first time indicating that the fall-out from the Chernobyl nuclear disaster in 1986 may have raised cancer rates in western Europe.
Travel of radio active cloud May 6,1986
The Power of the Atom
Energy stored in atom
Release of energy ELECTRICAL
ENERGY
At what cost?What are the Alternatives
Atoms for Peace Science concept Main Idea
Power of the AtomThe nucleus contains so much stored energy that can be released
Energy stored in the atom can be harnessed to generate electrical energy.
Nuclear Power(What is nuclear power?)
Nuclear Fission(Explain fission/fusion.)
Radioactive isotopes(What is an isotope? Why use
uranium? What does radioactive mean?
Nuclear reactors(How do nuclear reactors
generate electricity? Are these safe to use)
Nuclear waste(What are nuclear wastes? Is there a safe way to dispose of
these wastes?
U-235, when bombarded by neutrons, fissions or splits into two smaller nuclei and releases energy and starts a nuclear chain reaction.
C-11 20.3 minutes
C-12 Stable
C-13 StableC-14 5730.0 years
C-15 2.5 seconds
Isotope• a different version of the same element• same number of atoms but different number of neutrons
Atomic Mass: 12.0107 amu
Key Isotopes
nuclide 12C 13C 14C atomic mass 12.000 13.003 14.003
natural abundance 98.90% 1.10% trace
half-life stable stable 5730 yrs
URANIUM: U238.02u
U-235
U-238
Radioactive
Particles are emitted due to nuclear instability
Why Uranium?
a very heavy metal which can be used as an abundant source of concentrated energy.
occurs in most rocks in concentrations of 2 to 4 parts per million and is as common in the Earth's crust as tin, tungsten and molybdenum. Uranium occurs in seawater, and can be recovered from the oceans. discovered in 1789 by Martin Klaproth, a German chemist, in the mineral called pitchblende. It was named after the planet Uranus, which had been discovered eight years earlier.
formed in supernova about 6.6 billion years ago. While it is not common in the solar system, today its slow radioactive decay provides the main source of heat inside the Earth, causing convection and continental drift.
Uranium has a melting point is 1132°C.
heaviest of all the naturally-occurring elements (Hydrogen is the lightest). Uranium is 18.7 times as dense as water.
Natural uranium as found in the Earth's crust is a mixture largely of two isotopes: uranium-238 (U-238), accounting for 99.3% and uranium-235 (U-235) about 0.7%.
The isotope U-235 is important because under certain conditions it can readily be split, yielding a lot of energy. It is therefore said to be 'fissile' and we use the expression 'nuclear fission'.
U-238 decays very slowly, its half-life being about the same as the age of the Earth (4500 million years); barely radioactive, less so than many other isotopes in rocks and sand; generates 0.1 watts/tonne as decay heat, enough to warm the Earth's core. U-235 decays slightly faster.
Source: http://www.world-nuclear.org/education/uran.htm
http://www.odec.ca/projects/2006/wong6j2/nuclearAnimation.html
http://www.youtube.com/watch?v=igf96TS3ElsNuclear Power Generation
Uranium and Plutonium
Source: http://www.world-nuclear.org/education/uran.htm
Whereas the U-235 nucleus is 'fissile', that of U-238 is said to be 'fertile'.
This means that it can capture one of the neutrons which are flying about in the core of the reactor and become (indirectly) plutonium-239, which is fissile. Pu-239 is very much like U-235, in that it fissions when hit by a neutron and this also yields a lot of energy.
Sometimes a Pu-239 atom simply captures a neutron without splitting, and it becomes Pu-240. The longer the fuel stays in the reactor the more Pu-240 is in it.*
* The significance of this is that when the spent fuel is removed after about three years, the plutonium in it is not suitable for making weapons but can be recycled as fuel.
Write a paragraph explanation:
Should we have harnessed the power of the atom rather than coal? Would this have helped prevent our current environmental crisis? Knowing the nature of man, can we limit the use of the power of the atom for peace? How has people power been used to combat the use of nuclear power? Was this a mistake?
Should the Philippines invest in nuclear power? Why or why not?
Write a paragraph explanation:
•Should we have harnessed the power of the atom rather than coal? Would this have helped prevent our current environmental crisis?
•Knowing the nature of man, can we limit the use of the power of the atom for peace?
•How has people power been used to combat the use of nuclear power? Was this a mistake?
•Should the Philippines invest in nuclear power? Why or why not?