curium

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curium (symbol Cm) Synthetic radioactive metallic element of the actinide series in the periodic table. It was first made in 1944 by the US nuclear chemist Glenn Seaborg and his colleagues by the alpha-particle bombardment of plutonium-239 in a cyclotron. Silvery in colour, curium is chemically reactive, intensely radioactive and is toxic if absorbed by the body. It provides power for orbiting satellites. Properties: at.no. 96; r.d. (calculated) 13.51; m.p. 1340°C (2444°F); 14 isotopes, most stable Cm247 (half-life 1.6 × 107 yr).

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