BOHRIUM

'Bohrium' (IPA: ), also called 'eka-rhenium', is a chemical element in the periodic table that has the symbol 'Bh' and atomic number 107. It is a synthetic element whose most stable isotope, Bh-267, has a half-life of 22 seconds.

Contents

Chemistry

History

References

External links

Chemistry

Although chemistry is difficult when half-lives are measured in seconds, chromatography techniques were able to provide some data that Bohrium behaves like a member of group 7 of the periodic table.^[1]

History

It was synthesized in 1976 by a Soviet team led by Y. Oganessian at the Joint Institute for Nuclear Research at Dubna, who produced isotope ²⁶¹Bh with a half-life of 1-2 ms (later data gave a half life of around 10 ms).
They did this by bombarding bismuth-204 with heavy nuclei of chromium-54.
In 1981 a German research team led by Peter Armbruster and Gottfried Münzenberg at the Gesellschaft für Schwerionenforschung (Institute for Heavy Ion Research) in Darmstadt were also able to confirm the Soviet team's results and produce bohrium, this time the longer-lived Bh-262.
The Germans suggested the name ''nielsbohrium'' with symbol ''Ns'' to honor the Danish physicist Niels Bohr. The Soviets had suggested this name be given to element 105 (dubnium).
There was an element naming controversy as to what the elements from 101 to 109 were to be called; thus IUPAC adopted ''unnilseptium'' (IPA: , symbol ''Uns'') as a temporary, systematic element name for this element. In 1994 a committee of IUPAC recommended that element 107 be named ''bohrium''.
While this conforms to the names of other elements honoring individuals, where only the surname is taken, it was opposed by many who were concerned that it could be confused with boron. Despite this, the name ''bohrium'' for element 107 was recognized internationally in 1997.

References

1. "Chemistry of Hassium"

External links

★ WebElements.com - Bohrium

★ Apsidium - Bohrium

★ Los Alamos National Laboratory - Bohrium