Fission vs. Fusion

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Nuclear fusion and nuclear fission are two different types of energy-releasing reactions in which energy is released from high-powered atomic bonds between the particles within the nucleus. The main difference between these two processes is that fission is the splitting of an atom into two or more smaller ones while fusion is the fusing of two or more smaller atoms into a larger one. Nuclear fission is a class of nuclear change. Nuclear fission occurs when a very heavy nucleus splits into two smaller nuclei, each more stable than the original nucleus. Most fission reactions happen artificially by bombarding nuclei with neutrons. For a fission reaction, two conditions need to be satisfied. Critical mass of the substance. A relatively slow neutron is required to initiate the process. Nuclear fusion however is the reaction in which two or more nuclei combine together to form a new element with higher atomic number. The fusion of two nuclei with lower masses than iron generally releases energy, while the fusion of nuclei heavier than iron absorbs energy. This means that fusion generally occurs for lighter elements only, and likewise, that fission normally occurs only for heavier elements. For a nuclear fusion reaction to occur it is necessary to bring two nuclei so close that nuclear forces become active and glue the nuclei together. Nuclear forces are small-distance forces and have to act against the electrostatic forces where positively charged nuclei repel each other. This is the reason why nuclear fusion reactions occur mostly in high density, high temperature environment. Both nuclear fusion and fission have similar characteristics. Such as both fission and fusion nuclear reactions are chain reactions. A nuclear chain reaction occurs when one nuclear reaction causes an average of one or more nuclear reactions, thus leading to a self-propagating number of
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