[kyoo
r-ee-uhm] 
| a radioactive element not found in nature but discovered in 1944 among the products of plutonium after bombardment by high-energy helium ions. Symbol: Cm; atomic number: 96. |
| cu·ri·um (kyŏŏr'ē-əm) n. Symbol Cm A silvery metallic synthetic radioactive transuranic element. Its longest lived isotope is Cm 247 with a half-life of 16.4 million years. Atomic number 96; melting point (estimated) 1,350°C; valence 3. See Table at element. [After Marie Curie and Pierre Curie.] |
curium cu·ri·um (ky&oobreve;r'ē-əm)
n.
Symbol Cm
A metallic synthetic radioactive transuranic element. Atomic number 96; longest-lived isotope Cm 247; melting point (estimated) 1,350°C; valence 3,4.
curium (ky r'ē-əm) Pronunciation Key
Symbol Cm A synthetic, silvery-white, radioactive metallic element of the actinide series that is produced artificially from plutonium or americium. Curium isotopes are used to provide electricity for satellites and space probes. Its most stable isotope has a half-life of 16.4 million years. Atomic number 96; melting point (estimated) 1,350°C; valence 3. See Periodic Table. |
curium
synthetic chemical element of the actinoid series of the periodic table, atomic number 96. Undetected in nature, curium (as the isotope curium-242) was discovered (summer 1944) at the University of Chicago by Glenn T. Seaborg, Ralph A. James, and Albert Ghiorso in a plutonium isotope, plutonium-239, that had been bombarded by helium ions (alpha particles) in the 60-inch cyclotron at the University of California, Berkeley. It was the third transuranium element to be discovered
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