Mendelevium is an element with the symbol Md (formerly Mv) and the atomic number 101. It was named after Dimitri Ivanovich Mendeleev, who was responsible for the Periodic Table. Mendeleev's periodic system is the fundamental way to classify all the chemical elements. The name "mendelevium" was accepted by the International Union of Pure and Applied Chemistry (IUPAC). On the other hand, the proposed symbol "Mv" submitted by the discoverers was not accepted, and the IUPAC selected "Md" instead.
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, the latter being the more dominantly exhibited state in an aqueous solution (chromatography being the process used). Sometimes, mendelevium can even be shown to exhibit a monopositive (I) state. 256Md has been used to find out some of the chemical properties of this element while in an aqueous solution. Other isotopes of mendelevium, all radioactive, have been discovered, with 258Md being the most stable with a two-month half-life (about 55 days). Other isotopes range from 248 to 258 mass numbers and half-lives from a few seconds to about 51 days. The original 256Md had a half-life of 87 minutes.
The radioactivity of the trivalent element, mendelevium, is definitely noteworthy. It was expected that the reaction would be253Es (α,n) 255Md, where 255Md was α-active with a t½ of 5 minutes and the corresponding α-energy. No such α-activity was observed, but the 101 fraction showed spontaneous fission representing a t½ less than 3 hours. Because spontaneous fission was also observed in the fraction containing fermium, the α-bombardment of 253Es was supposedly produced 256Md. The latter underwent electron capture to become 256Fm, which then decayed by spontaneous fission. So 256Fm was produced by the decays of cyclotron-synthesized mendelevium.
The base value of each unit of ranges between 25 and 75Ð per unit, with up to 6 units being found at any one time.
Presence on Mars: Very Rare
|Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6|
|Group 5||| Americium | Anthraximite | Areanetium Dieinsteinium | Areanetium Ferrocrete | Areanetium Mendelite | Berkelium | Bohrium | |Californium | Curium | Darmstadtium | Einsteinium | Fermium | Fermium Hasside | Ferro-plat Alloy | Hassium | Lawrencium | |Meitnerium | Meitnerium Golgathide | Mendelevium | Neptunium | Nobelium | Plutonium | Roentgenium | Seaborgium | |Transuranic Alloblast ||