from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. Plural form of isotope.


Sorry, no etymologies found.


  • (Presumably, the need for a license is a matter of degree, given that our own bodies contain radioactive potassium-40, and given that the walls of most buildings contain the radioactive isotopes from the natural uranium-238 and thorium-232 decay chains).

    Archive 2009-04-01

  • More precise dating based on carbon isotopes is now under way.

    The Dodo Life of Long Ago

  • Small portable lead caskets weighing only 20 to 30 lbs. have been developed, which contain isotopes that emit radiations comparable to a 100,000 volt X-ray machine.

    The Peacetime Applications of Atomic Energy

  • The English scientist in question now showed that two or more elements might quite well be identical in a chemical respect and occupy the same place in the System - or, as he called it, be "isotopes" - but nevertheless be unlike one another as regards both atomic weight and certain physical properties.

    Nobel Prize in Chemistry 1921 - Presentation Speech

  • Some isotopes from a nuke blast are not healthy for anyone, if we can’t keep them from testing which is the current consensus, even with Bush’s June 2. 7Kton non nuke test, we should at least keep it deep underground

    Think Progress » Bush ‘Doubts’ He’ll See Gore Movie; Wants To ‘Set Aside’ Global Warming Science

  • The number of neutrons in an atom's nucleus is less fixed than the number of protons: many elements have different versions, called isotopes, with different numbers of neutrons.

    Natural Enchantment

  • Atoms of any given element can come in different versions called isotopes, which have differing numbers of neutrons, but always the same number of protons.


  • Thermal reactors are powered by lower-grade uranium isotopes, which is disadvantageous because the by-product is nuclear waste never a very popular commodity with inhabitants of an island nation, and also because Japan is still left with the problem of importing nuclear fuel, usually from Australia.

    Letter from Tsuruga » Japundit Blog

  • Seeing that the isotopes had identical chemical properties, chemists accepted their discovery with tranquillity - indeed, after it had been established that the atomic weights of the isotopes were all whole numbers, with a degree of satisfaction, for thereby a justification was afforded for Prout's very attractive hypothesis, enunciated more than 100 years ago, that the atomic weights of all the elements were multiples of that of hydrogen and consequently whole numbers.

    Nobel Prize in Chemistry 1934 - Presentation Speech

  • Hair analysis relies on the fact that hydrogen - an element found in water - comes in slightly different chemical forms called isotopes.

    CBC | Top Stories News


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