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{%type%} Definitions

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n. - An element of the series of heavy metallic elements of increasing atomic number

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Usage examples (39)
  • The chemical behaviour of actinium is similar to that of the rare earths, particularly lanthanum.
  • Hahn's radiothorium and actinium salts also followed him to Emil Fischer's laboratory in Berlin. 30
  • In France, Debierne had discovered actinium and Giesel claimed to have found a different element, emanium.
  • However, this new series of closely associated elements does not begin with uranium 92, but with actinium 89.
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