isotope

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Isotope

Pronunciation

• (UK) IPA ^(key): /ˈaɪ.sə.təʊp/
• (US) IPA ^(key): /ˈaɪ.sə.toʊp/

• Audio (US)

  (file)

Noun

Singular isotope

Plural isotopes

1. (chemistry); (physics) Isotopes are atomic cores belonging to the same element that have the same number of protons, but have a different number of neutrons.

   Uranium 235 and uranium 238 are isotopes of uranium.

   Deutherium is an isotope of oxygen that has two neutrons.