1955, Modern Latin, in honor of Dmitri Ivanovich Mendeleev.
mendelevium men·de·le·vi·um (měn'də-lē'vē-əm)
n.
Symbol Md
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) Symbol Md 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).