Fr

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Definition
  1. Noun:
    • A radioactive element of the alkali-metal group discovered as a disintegration product of actinium: "Fr" is the chemical symbol for the element francium. It is a highly unstable, radioactive metal.
Usage
  • The symbol "Fr" is used primarily in scientific contexts, such as chemistry and physics, to represent the element francium in the periodic table, formulas, and discussions of radioactive decay chains.
Examples of Usage
  • Noun:
    • Francium (Fr) is the least stable of the naturally occurring elements.
    • The isotope Fr-223 is found in the decay chain of uranium-235.
    • In the periodic table, Fr is located in group 1, the alkali metals.
Advanced Usage
  • Scientific Notation: "Fr" is used in nuclear equations to denote francium atoms or ions.
    • The decay of actinium-227 produces Fr-223 through alpha decay.
Variants and Related Words
  • Francium (n): The full name of the element represented by the symbol "Fr".
    • Francium is extremely rare due to its short half-life.
Synonyms
  • Element 87: A synonym referring to francium by its atomic number.
  • Alkali metal: The group to which francium belongs, though this is a category, not a direct synonym for "Fr" itself.
Noun
  1. a radioactive element of the alkali-metal group discovered as a disintegration product of actinium

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