Examine individual changes

'{{Merge|Binding energy|date=October 2009}} {{About|nuclear energy in physics|the use of nuclear fission as a power source|Nuclear power|the sculpture|Nuclear Energy (sculpture)}} '''Nuclear energy''' is released by the splitting (fission) or merging together (fusion) of the [[Atomic nucleus|nuclei]] of [[atom]](s). The conversion of nuclear [[mass]] to energy is consistent with the [[mass-energy equivalence]] formula ''ΔE''&nbsp;=&nbsp;''Δm.c''², in which ''ΔE'' = energy release, ''Δm'' = [[mass defect]], and ''c'' = the [[speed of light]] in a [[vacuum]] (a [[physical constant]]). Nuclear energy was first discovered by [[France|French]] physicist [[Henri Becquerel]] in 1896, when he found that photographic plates stored in the dark near [[uranium]] were blackened like [[X-ray]] plates, which had been just recently discovered at the time 1895.<ref>{{cite web |url=http://www.aip.org/history/curie/resbr1.htm |title=Marie Curie - X-rays and Uranium Rays''' |publisher=aip.org |accessdate=2006-04-10}}</ref> [[Nuclear chemistry]] can be used as a form of [[alchemy]] to turn [[lead]] into [[gold]] or change any atom to any other atom (albeit through many steps).<ref>[http://chemistry.about.com/cs/generalchemistry/a/aa050601a.htm Turning Lead into Gold]</ref> [[Radionuclide]] (radioisotope) production often involves irradiation of another [[isotope]] (or more precisely a [[nuclide]]), with [[alpha particle]]s, [[beta particle]]s, or [[gamma ray]]s. [[Iron]] has the highest binding energy per [[nucleon]] of any atom. If an atom of lower average binding energy is changed into an atom of higher average binding energy, energy is given off. The chart shows that fusion of [[hydrogen]], the combination to form heavier atoms, releases energy, as does fission of uranium, the breaking up of a larger nucleus into smaller parts. Stability varies between isotopes: the isotope [[Uranium-235|U-235]] is much less stable than the more common [[Uranium-238|U-238]]. [[Image:Binding energy curve - common isotopes.svg|500px]] Nuclear energy is released by three ''exoenergetic'' (or [[exothermic]]) processes: * [[Radioactive decay]], where a neutron or proton in the [[radioactive]] nucleus decays spontaneously by emitting either particles, [[electromagnetic radiation]] (gamma rays), [[neutrinos]] (or all of them) * [[nuclear fusion|Fusion]], two atomic nuclei fuse together to form a heavier nucleus * [[nuclear fission|Fission]], the breaking of a heavy nucleus into two (or more rarely three) lighter nuclei == References == {{reflist}} [[ar:طاقة نووية (فيزياء)]] [[bn:পারমাণবিক শক্তি]] [[bg:Ядрена енергия]] [[cs:Jaderná energie]] [[fa:انرژی هسته‌ای]] [[kn:ಪರಮಾಣು ಶಕ್ತಿ]] [[ml:ആണവോർജ്ജം]] [[pl:Energia jądrowa]] [[ru:Ядерная энергия]] [[simple:Nuclear energy]] [[sv:Kärnenergi]] [[ta:அணுக்கரு ஆற்றல்]] [[uk:Атомна енергія]] [[ug:يادرو ئېنېرگىيىسى]]'