Asked by AnisaPhysics πŸš€

What is the difference between nuclear fission and nuclear fusion?

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Sumangla Kapoor

Graduate from University of Delhi and savvy tutor

Fission is a process in which a heavy nucleus of an element splits into two or more stable elements. This fission reaction is associated with the release of energy. For example, the process of U235 fission is triggered by hitting U235 by a slow-moving neutron. It gives Barium( 144), Krypton (89) and three neutrons along with 210Mev of energy. Fusion: Two light elements such as Hydrogen nucleus fuse or combine to form a heavier nucleus. This reaction takes place in stars and our sun as well. Two hydrogen nucleus combine to form heavy hydrogen along with the release of energy they continue to fuse again until a stable nucleus of Helium is formed. The most important question is why energy is released??? Why is He stable?..and please do think many more why and How?.

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Josh Prince

I want to help you achieve amazing GCSE results!

Fission is when an unstable nucleus spontaneously decomposes into two or more smaller, more stable nuclei. Eg: Uranium-235 undergoes nuclear fission to become Barium-139 and Krypton-94 plus 3 neutrons. In summary a big unstable nucleus falls apart (decays) and becomes two or more smaller nuclei. Fusion is when two or more small nuclei fuse together to form a bigger nucleus. E.g. Hydrogen nuclei undergo fusion to form a helium nucleus. This process requires a lot more input energy than fission. Essentially fission and fusion are opposites of each other. In fission nuclei decompose and in fusion the nuclei fuse together.

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