transmutation of elements

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transmutation of elements,

conversion of one chemical element into another. The expression has both historical and contemporary significance. The transmutation of certain metals into gold by means of a substance called the philosopher's stone was one of the two most ambitious quests of the alchemists (see alchemyalchemy
, ancient art of obscure origin that sought to transform base metals (e.g., lead) into silver and gold; forerunner of the science of chemistry. Some scholars hold that it was first practiced in early Egypt and others that it arose in China (in the 5th or 3d cent. B.C.
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); the other was for the elixir of life that would cure all diseases, restore youth to the aged, and make youthfulness eternal. The possibility of finding the philosopher's stone harmonized with ideas long generally held, and honest and able persons once hoped to find it. Now and then a charlatan professed to have found it.

In modern times it has been found that a transmutation from one element to another actually does occur in the process of natural radioactivityradioactivity,
spontaneous disintegration or decay of the nucleus of an atom by emission of particles, usually accompanied by electromagnetic radiation. The energy produced by radioactivity has important military and industrial applications.
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. Transmutation of elements can be achieved artificially by the bombardment of elements with high-speed particles or ions using a particle acceleratorparticle accelerator,
apparatus used in nuclear physics to produce beams of energetic charged particles and to direct them against various targets. Such machines, popularly called atom smashers, are needed to observe objects as small as the atomic nucleus in studies of its
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. Both artificial and natural transmutations involve changing the number of protons in the atomic nucleusnucleus,
in physics, the extremely dense central core of an atom. The Nature of the Nucleus

Atomic nuclei are composed of two types of particles, protons and neutrons, which are collectively known as nucleons.
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. The transuranium elementstransuranium elements,
in chemistry, radioactive elements with atomic numbers greater than that of uranium (at. no. 92). All the transuranium elements of the actinide series were discovered as synthetic radioactive isotopes at the Univ.
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 are created in this manner. When a nucleus is bombarded with neutrons from an atomic pile or nuclear reactor, some of the neutrons will be absorbed, resulting in an unstable nucleus. The nucleus then becomes more stable by converting one of its neutrons into a proton by beta decay, becoming a nucleus of the next heavier element in the process.

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