mendelevium men·de·le·vi·um (měn'də-lē'vē-əm)
A synthetic radioactive element; its most stable isotope is Md 258 with a half-life of 56 days. Atomic number 101.
|mendelevium (měn'də-lē'vē-əm) Pronunciation Key
A synthetic, radioactive metallic element of the actinide series that is produced by bombarding einsteinium with helium ions. Its most stable isotope is Md 258 with a half-life of approximately 51.5 days. Atomic number 101. See Periodic Table.
synthetic chemical element of the actinoid series of the periodic table, atomic number 101. It was the first element to be synthesized and discovered one atom at a time. Not occurring in nature, mendelevium (as the isotope mendelevium-256) was discovered (1955) by Albert Ghiorso, Bernard G. Harvey, Gregory R. Choppin, Stanley G. Thompson, and Glenn T. Seaborg at the University of California, Berkeley, as a product resulting from the helium-ion bombardment of a minute quantity (1,000,000,000 atoms) of einsteinium-253 (atomic number 99).
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