Hassium elements

Hassium, element 108, does not exist in nature but must be made in a particle accelerator. It was first created in 1984 and can be made by shooting mag-nesium-26 (ifMg) atoms at curium-248 ( HCm) atoms. The collisions between these atoms produce some hassium-265 (io Hs) atoms. The position of hassium in the periodic table (see Fig. 2.20) in the vertical column containing iron, ruthenium, and osmium suggests that hassium should have chemical properties similar to these metals. However, it is not easy to test this prediction—only a few atoms of hassium can be made at a given time and they last for only about 9 seconds. Imagine having to get your next lab experiment done in 9 seconds ... 

DiiUmann Ch, Briichle W, Dressier R et al (2002) Chemical investigation of hassium (element 108). Nature 418 859... 

Hassium - the atomic number is 108 and the chemical symbol is Hs. The name derives from the Latin Hassia for the German state of Hesse , whose former capital was Darmstadt. The element was first synthesized by German physicists at the GSI (Center for Heavy-Ion Research) Lab at Darmstadt, Germany in 1984 using the nuclear reaction ° Pb ( Fe, n) Hs. The longest half-life associated with this unstable element is 11 minute Hs. 

Most of the chemical and physical properties of imniloctium (hassium) are unknown. What is known is that its most stable isotope (hassium-108) has the atomic weight (mass) of about 277. Hs-277 has a half-life of about 12 minutes, after which it decays into the isotope seaborgium-273 through either alpha decay or spontaneous fission. Hassium is the last element located at the bottom of group 8, and like element 107, it is produced by a cold fusion process that in hassium s case is accomplished by slamming iron (Fe-58) into particles of the isotope of lead (Pb-209), along with several neutrons, as follows ... 

In December 1998 the Lawrence Berkeley Laboratory sent a supply of plutonium-244 and calcium-48 to Russian scientists at the Joint Institute of Nuclear Research in Dubna, Russia. The Russians bombarded the plutonium with ions of calcium, which, after some time, produced a single atom of ununquadium-289. Uuq has a half-life of just 30 seconds, after which it decays successively into element 112 (ununbium), element 110, (darmstadtium), and element 108 (hassium). The Russian nuclear laboratory later synthesized several atoms of other isotopes of Ununquadium. 

Element 110 was claimed earlier, but less convincingly, at both Dubna and Berkeley.) Element 108 is called hassium, after the German state of Hesse wherein Darmstadt is situated element 109 is named meitnerium, for Lise Meitner, who was the first to realize that uranium undergoes nuclear fission. Beyond this, the new elements have yet to be named. 

CAS 54037-57-9[. Hassium is a chemical clement in the periodic table that has the symbol Hs and atomic number 108. It is a synthetic element whose most stable isotope is Hs-265. with a half-life of 2 ms. It was first synthesized in 1984 by a German research team led by Peter Armbruster and Gottfried MUnzenbcrg at Ihe Institute for Heavy Ion Research at Darmstadt The name hassium was proposed by them, derived from the... 

The chemistry of hassium has been studied recently using the formation of chemically stable, volatile HSO4, a property of Group 10 (VIII) elements. Thermo-chromatography has shown Hs04 to be less volatile than Os04, a result in agreement with some relativistic predictions but not others (Fig. 15.17). 

Kratz, J.V. Chemistry of Seaborgiuim and Prospects for Chemical Studies of Bohrium and Hassium , In Proceedings of The Robert A. Welch Foundation 41st Conference on Chemical Research, The Transactinide Elements , Houston, Texas, 27-28 October 1997, pp. 65. 

Yakushev, A.B., Vakatov, V.I., Vasko, V., Lebedev, V.Ya., Timokhin, S.N., Tsyganov, Yu.S., Zvara, I. "On-line Experiments with Short-lived Osmium Isotopes as a Test of the Chemical Identification of the Element 108 - Hassium" In Extended Abstracts of "1st International Conference on Chemistry and Physics of the Transactinide Elements", Seeheim, Germany, 26-30 September 1999, P-M-17. 

Element 108 (hassium) was produced by the same group in 1984 by the reactions... 

At this time, to name an element a researcher or team of researchers must be certified by lUPAC as the discoverers of that element, at which time they are free to name the compound. The elements 104-109 were subject to a naming controversy. The originally proposed names of these elements by lUPAC were, in order, dub-nium, joliotium, rutherfordium, bohrium, hahnium, and meiterium. The names which appear on the current periodic table are, in order, rutherfordium (Rf), dubnium (Db), seaborgium, bohrium (Bh), hassium (Hs), and meitnerium (Mt). 

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