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|Atomic Number:||101||Atomic Symbol:||Md|
|Atomic Weight:||258||Electron Configuration:||2-8-18-32-31-8-2|
|Melting Point:||oC||Boiling Point:||oC|
|Description:||Man made radioactive metal.|
History(Dmitri Mendeleev) Mendelevium, the ninth transuranium element
of the actinide series discovered, was first identified by Ghiorso, Harvey,
Choppin, Thompson, and Seaborg in early in 1955 during the bombardment of the
isotope 253Es with helium ions in the Berkeley 60-inch cyclotron. The isotope
produced was 256Md, which has a half-life of 76 min. This first identification
was notable in that 256Md was synthesized on a one-atom-at-a-time basis.
- Fourteen isotopes are now recognized.
- 258Md has a half-life of 2 months.
- This isotope has been produced by the bombardment of an isotope of
einsteinium with ions of helium.
- Eventually enough 258Md should be made to determine its physical properties.
Uses256Md has been used to elucidate some of the chemical properties of
mendelevium in aqueous solution.
PropertiesExperiments seem to show that the element possesses a
moderately stable dipositive (II) oxidation state in addition to the tripositive
(III) oxidation state, which is characteristic of the actinide elements