|Boiling Point: unknown
Melting Point: 1100oK, 827oC, 1521oF
Elec. Energy Level: 2, 8, 18, 32, 31, 2
Isotopes: 18 + None Stabel +1 meta state
Heat of Vaporization: unknown
Heat of Fusion: unknown
Specific Heat: unknown
Atomic Radius: unknown
Ionic Radius: unknown
Electronegativity: 1.3 (Pauling), 1.2 (Allrod Rochow)
1s2 2s2p6 3s2p6d10 4s2p6d10f14 5s2p6d10f13 6s2p6 7s2
Mendelevium (for Dmitri Mendeleyev, surname commonly spelt as Mendeleev, Mendeléef, or even Mendelejeff, and first name sometimes spelt as Dmitry or Dmitriy) was first synthesized by Albert Ghiorso (team leader), Glenn T. Seaborg, Bernard G. Harvey, Gregory R. Choppin, and Stanley G. Thompson in early 1955 at the University of California, Berkeley. They bombarded the isotope 253Es with helium ions (alpha particles) in the Berkeley 60-inch cyclotron, ejecting a neutron and yileding a nucleus of 256Md. 256Md has a half-life of 78 minutes. This first identification was notable in that 256Md was synthesized on a one-atom-at-a-time basis. The most stable isotope is 258Md with a half-life of 51.5 days.
Researchers have shown that mendelevium has a moderately stable dipositive (II) oxidation state in addition to the more characteristic (for actinide elements) tripositive (III) oxidation state. 256Md has been used to find out some of the chemical properties of this element while in an aqueous solution. There are no other uses of mendelevium and only trace amounts of the element have ever been produced.
Since only small amounts of mendelevium have ever been produced, it currently has no uses outside of basic scientific research.
Eighteen radioisotopes of mendelevium have been characterized, with the most stable being 258Md. 258Md produced by the bombardment of an isotope of einsteinium with ions of helium has a half-life of 51.5 days. It decays into 254Es through alpha decay or decays through spontaneous fission. 260Md has a half-life of 31.8 days and 257Md a half-life of 5.52 hours. All of the remaining radioactive isotopes have half-lifes that are less than 97 minutes, and the majority of these have half-lifes that are less than 5 minutes. This element also has 1 meta state, 258mMd (t½ 57 minutes). The isotopes of mendelevium range in atomic weight from 245.08083 amu (245Md) to 262.10887 amu (262Md). Eventually enough 258Md should be made to determine its physical properties.
Mendeleyev's 1872 Periodic Table
Atomic Radius (Å): unknown
Electrochemical Equivalent: 3.21g/amp-hr
Atomic Mass Average: 258