Chemical Element: polonium

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Chemical-Element Information

Symbol: Po
Atomic number: 84
Year discovered: 1898

Discovered by: Marie Sklodowska Curie (1867-1934), Polish-born French chemist; and Pierre Curie (1859-1906), French chemist in Paris.

• Marie Curie discovered that although pure uranium compounds were always radioactive only to the extent that uranium was present, some uranium ores produced far more radioactivity than could be accounted for by the uranium present.
• It seemed to her that the ores must contain other elements (in small quantities or they would have been discovered earlier) that were much more intensely radioactive than uranium.
• In July, 1898, the Curies detected such an element, which they called “polonium” in honor of Marie Curie’s native land.
• It required several tons of pitchblende to produce very small amounts of polonium.
• Polonium is used in nuclear physics as a source of alpha radiation that is practically exempt from penetrating rays.
• Irène Curie (1900-1956) and her husband Frédéric Joliet-Curie (1900-1958), discovered artificial radioactivity in 1934 by bombarding aluminum, boron, and magnesium with alpha rays of Po.
• While working as her mother’s assistant, Irène met Frédéric Joliet, another assistant and they were married in 1926.
• Since Marie and Pierre Curie had no sons and since Joliot did not wish that eminent name of Curie to die out, he changed his name to Joliot-Curie.
• When ill health forced her mother to retire, Irène succeeded to her post of professor at the Sorbonne in Paris.
• Marie had taken over the post when Pierre was killed, the first woman ever to hold such a position at the Sorbonne.
• Irène and Frédéric worked together (just as her parents had done) on further researches into radioactivity.
• Both died in Paris, Irène on March 17, 1956, at the age of 52 (of leukemia, like her mother, probably induced by overexposure to energetic radiation) and Frédéric on August 14, 1958, at the age of 58.
• Mixtures of polonium with beryllium and other light elements are used as sources of neutrons.
• Polonium also has been used to ionize air, mainly in order to avoid the accumulation of electrostatic charges.
• For the detection of polonium and radium, Marie Curie (her husband by then having been run over and killed by a horse-drawn vehicle) received the Nobel Prize for chemistry in 1911.

Name in other languages:

French: polonium

German: Polonium

Italian: polonio

Spanish: polonio

Information about other elements may be seen at this Chemical Elements List.

A special unit about words that include chemo-, chem- may be seen here.