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isotope

/ˈaɪ.sə.təʊp/
IELTSAcademic
noun

An isotope is a form of a chemical element with the same number of protons but a different number of neutrons. Isotopes have the same atomic number but different atomic mass.

  • Carbon-14 is a radioactive isotope.
  • Hydrogen has three common isotopes.
  • Some isotopes are used in medical scans.

Adinary Nuance

Isotope is not the same as element. An element is the broad chemical substance, while an isotope is one version of that element with a different neutron count. It is also different from atom, which is a single particle, and molecule, which is two or more atoms joined together.

In other languages

Vietnamese
đồng vị
Spanish
isótopo
Chinese
同位素
Japanese
同位体
Korean
동위 원소

Etymology

The word isotope was coined in the early 1900s from Greek roots meaning “same place.” It refers to elements that occupy the same place in the periodic table.

Common phrases

radioactive isotopestable isotopecarbon isotopeisotope ratio

Synonyms

Related words

Frequently asked questions

What is the difference between an isotope and an element?
An element is the chemical type. An isotope is one version of that element with a different number of neutrons.
Are isotopes always radioactive?
No. Some isotopes are stable and do not break down over time.
Is isotope a common word in science writing?
Yes. It is common in chemistry, physics, medicine, and environmental science.