“mendelevium”的意思、由来-百科全书

mendelevium

chemical element

(Md),

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).

In about a dozen repetitions of the experiment, the team of scientists produced 17 atoms of mendelevium, which were identified by the ion-exchange adsorption–elution method (mendelevium behaved like its rare-earth homologue thulium). Other isotopes of mendelevium, all radioactive, have been discovered. The stablest is mendelevium-258 (two-month half-life). Studied by means of radioactive tracer techniques, mendelevium exhibits a predominant +3 oxidation state, as would be expected by its position in the actinoid series; a moderately stable +2 oxidation state is also known.

atomic number

101

stablest isotope

258

oxidation states

+2, +3

electronic config.

【Rn】5f¹³7s²

词条	mendelevium
释义	mendelevium chemical element (Md), 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). In about a dozen repetitions of the experiment, the team of scientists produced 17 atoms of mendelevium, which were identified by the ion-exchange adsorption–elution method (mendelevium behaved like its rare-earth homologue thulium). Other isotopes of mendelevium, all radioactive, have been discovered. The stablest is mendelevium-258 (two-month half-life). Studied by means of radioactive tracer techniques, mendelevium exhibits a predominant +3 oxidation state, as would be expected by its position in the actinoid series; a moderately stable +2 oxidation state is also known. atomic number 101 stablest isotope 258 oxidation states +2, +3 electronic config. 【Rn】5f¹³7s²
随便看	Masséna, André, duc de Rivoli, prince d'Essling mast mast cell mastectomy Mastenbroek, Hendrika Master E.S. Master of Flémalle Master of Moulins master of the animals Master of the Housebook Master of the Playing Cards Master of the Revels Masters and Johnson master's degree Masters, Edgar Lee Masterson, Bat Masters Tournament Masters Tournament winners Masterton mastic mastiff mastiff bat Mastigophora mastitis mastodon