Nuclear+Fission+and+Fusion

=//Nuclear Fission and Fusion//=

__**Nuclear Fission**__
Nuclear fission is the process of a nuclear reaction or radioactive decay, it is when the nucleus of an atom splits into more smaller nuclei sometimes producing excess neutrons and photons in the form of gamma rays, as all this is happening a large amount of energy is released which can cause some of the released neutrons to hit another nucleus causing that one to become too unstable causing that one to split as well causing a chain reaction. These reactions can be harnessed to produce energy in reactors or released in the form of nuclear weapons. Fission releases energy when the nuclei have combined mass greater then that of iron and will absorb energy with anything less.

-The Discovery of Fission
Nuclear fission was discovered in the year 1938 after almost 50 years of improving people's knowledge of the atom, it started in 1911 when Ernest Rutherford displayed the model of the atom which had a small dense nucleus that contained protons and neutrons that had negatively charge electrons orbiting around it. This model was then improved on by Niels Bohr in the year 1913 when he said that the electrons move between different layers in the atom and were being controlled by electric forces instead of gravity. After many years and much work done by many different scientists Rutherford had learned that the nucleus was capable of going through different kinds of radioactive decay letting it change to a different element (also known as transmutation) it was also learned that during reaction some mass was lost during the reaction proving that energy did in fact have mass (The famous equation by Albert Einstein E=mc^2) however this release of energy was unable to be harnessed in a large scale. After that scientists began to shoot particles at atoms in attempt to cause them to split forming another nucleus. Fission was official named by Otto Frisch as an analogy to binary fission in the biological sciences.

__**Nuclear Fusion**__
Nuclear fusion is practically the opposite of nuclear fission, it is the process of two or more nuclei joining (or fusing) together to form one heavier nucleus. This reaction also produces a large amount of energy and in fact the process that occurs in active stars, Fusion only releases energy when the two nuclei have a combined mass lower then that of iron and when it is above that mass it absorbs energy. this means that fusion generally only happens with smaller elements such as hydrogen. At this point in time it it extremely difficult to recreate the conditions required to accomplish nuclear fusion so the process that stars undergo has not been recreated on this planet, yet.

-The Requirements for Fusion to Occur
In order for fusion to occur the electric forces must be overcome. Because of this electric force nuclei repel each other at large distances however if the nuclei are brought close enough together the nuclear force will kick in which is much stronger then the electric force. The reason that fusion only works well with small nucleus is because the smaller the nucleus the larger the surface area to volume ratio is allowing the other nuclei more room to grab on. however because both the nucleus are positively charged they repel each other more strongly the closer they get to each other creating a large energy barrier called a the Coulomb Barrier. for the deuterium-tritium fuel this energy barrier is around 0.1 MeV, in order to get past this barrier the nucleus would have to be heated up to around 120 million kelvins which is not yet easily accomplished.

-Fumbles12 (Keegan Keyser)

//References//

 * 1) Brad Langdale, 2012, []
 * 2) Dianne, September 14th 2010, []
 * 3) John Fuller, []

=//Nuclear Fission and Fusion//=

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Both fission and fusion have started a new age for humanity. It has created the atomic bomb which lead to hydrogen bombs. It started with the thought of what would happen if you shot an neutron at the largest particle known uranium. The result was the atom of uranium splitting was a release of energy and neutrons which creates a reaction with more uranium atoms being split. This is fission. It is used as a electricity power is some countries. It is also used to start the nuclear fusion reaction in hydrogen bombs. These type of reactions is also used to make radioactive isotopes for medical reasons. The act of making it decay into different elements is called artificial decay. The waste of nuclear fission has to be contained because it is radioactive and dangerous to people to be exposed to it. There is also the possibility for a nuclear power plant to melt down and cause environmental harm.======

Fusion is the opposite of fission, it is combining two small elements to create energy. Using intense heat you can combine the smaller atoms and create energy. Which will cause a chain reaction creating more and more energy till all the atoms have been changed. This is what is used in hydrogen bombs. It is not yet able to be used for electricity power until there is a way to contain the power it releases. It also takes so much energy to start the fusion reaction that it is difficult to start the reaction in a controlled manner. Some ways that physicists are trying to heat it to this extreme is to use high powered lasers to compress the atoms together which will in turn release the energy in heat in nuclear fusion. There is also many different ways that scientists are trying to gain the energy of nuclear fusion for a sustainable resource. Anthony Schoepp

//References//

 * 1) Brad Langdale, 2012, []
 * 2) 2012, []
 * 3) 2011, []