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Nuclear FissionNuclear FissionBy Greg Schweiker and Josh Helzner

Nuclear fission is when a reaction in the nucleus causes a split into two lighter nuclei

Occurs when a nucleus has too many protons and neutrons to stay stable.

The mass is converted into energy. To undergo fission you need a heavy

nuclei. Lighter nuclei go through another process called fusion.

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Conditions for fission to occur There needs to be a critical mass (Critical-

having enough mass to sustain a reaction). Has to have high speed neutrons, will no

work with low speed neutrons.

Born in Vienna, Austria on November 7th, 1878

Went to University of Vienna Was one of the people to discover nuclear

fission. She unleashed the possibility of the nuclear reactor.

Her discoveries led to the development of the atomic bomb.

Born in Frankfurt, Germany on March 8th, 1879

Went to Humboldt University of Berlin Published the first report on his discovery of

the Uranium Z. Partner of Lise Meitner for a short time. Considered the “Father of

Nuclear Chemistry”. Won the Nobel Prize in 1944 for

his discovery and work on nuclear fission.

Born in Budapest, Austria-Hungary on February 11, 1898

Studied at Humboldt University of Berlin Worked on the first nuclear reactor, and the

atomic bomb. One of the first scientists

to realize the true power, and dangers nuclear reactions may have.

Discovered on December 17, 1938 By Otto Hahn and Fritz Strassman (Assistant).

Found when they bombarded Uranium-235 with neutrons.

Lise Meitner wrote explanation of this new reaction and coined the term “fission”.

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Otto Hahn and Strassman were performing extra tests on the bombarded uranium.

Lise and Hahn predicted that the experiment would result in the element radium, but it instead ended with the lighter elements of barium and krypton.

Hahn realized that the uranium atoms split into much smaller atoms.

This split released neutrons and a very large amount of energy. There was also a loss of some mass.

Meitner expected a release of energy due to Einstein's famous equation, E= mc2.

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Nuclear weapons, atomic bombs, and power plants (Used Cautiously).

Nuclear fission of uranium is used in nuclear reactors due to its ability to contain a nuclear chain.

This nuclear chain allows the molecules to sustain themselves.

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Nuclear Fusion- A nuclear reaction when atomic nuclei of a low atomic number fuse together to form a heavy nucleus with the release of energy

Nuclear fusion is seen in stars, supernovas, and the sun.

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Other Alternatives Continued The energy released in nuclear fusion is

about three to four times greater than fission.

Nuclear fusion is safer than fission It is, however, more difficult to perform.

http://ansnuclearcafe.org/2012/02/14/lise-meitners-fantastic-explanation-nuclear-fission/

http://chemwiki.ucdavis.edu/Physical_Chemistry/Nuclear_Chemistry/Fission_and_Fusion

http://www.diffen.com/difference/Nuclear_Fission_vs_Nuclear_Fusion

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