radium summary

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Below is the article summary. For the full article, see radium.

radium, Chemical element, heaviest alkaline earth metal, chemical symbol Ra, atomic number 88. It was discovered by Marie Curie and her husband, Pierre Curie, in 1898 and isolated by 1910. All its isotopes are radioactive (see radioactivity). Radium does not occur free in nature but occurs in natural ores such as pitchblende as a disintegration product of radioactive decay of heavier elements, including uranium. Chemically it is highly reactive and has valence 2 in all of its compounds. Its use in medicine (see radiation therapy; radiology; nuclear medicine) has declined because of its cost, and its use in consumer goods (to illuminate watch and clock hands and numbers, as well as instrument dials) was halted because it can cause radiation injury. It is still used for some radiography and as a source of neutrons.

Marie Curie Summary

Marie Curie was a Polish-born French physicist, famous for her work on radioactivity and twice a winner of the Nobel Prize. With Henri Becquerel and her husband, Pierre Curie, she was awarded the 1903 Nobel Prize for Physics. She was the sole winner of the 1911 Nobel Prize for Chemistry. She was