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isotope Line breaks: iso|tope
Pronunciation: /ˈʌɪsətəʊp/

Definition of isotope in English:


Each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element: some elements have only one stable isotope radioactive isotopes of caesium, strontium, and plutonium
More example sentences
  • Radioactive elements have different isotopes that decay at different rates.
  • Beta radiation is the emission of an electron from the nucleus of a radioactive isotope.
  • The nuclei of the hydrogen isotopes are the proton, the deuteron, and the triton.


1913: coined by F. Soddy, from iso- 'equal' + Greek topos 'place' (because the isotopes occupy the same place in the periodic table of elements).



Pronunciation: /ʌɪsəˈtɒpɪk/
Example sentences
  • Ecologists see these isotopic ratios of carbon, hydrogen, oxygen, and nitrogen as signatures.
  • Radiocarbon dating relies on the fact that carbon exists naturally in several isotopic forms.
  • During subsequent logging, samples of core were selected for sectioning and for geochemical, mineralogical and isotopic analysis.


Pronunciation: /ʌɪsəˈtɒpɪk(ə)li/
Example sentences
  • Likewise, isotopically substituted lipid membranes can be differentiated from protein adlayers and even each other with the proper selection of unique isotopic labels.
  • During interglacial periods the ice caps melt and return the isotopically light water to the oceans, where it mixes rapidly.
  • With its origin in the local electron distribution, the chemical shift is a sensitive reporter of the chemical environment of isotopically labeled atoms.


Pronunciation: /ʌɪˈsɒtəpi/
Example sentences
  • It is an excellent piece of work which considers loop and quasigroup identities that are invariant under isotopy, proving a number of very interesting results.

Words that rhyme with isotope


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