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Meitnerium

physical science Maturity 11-13 Next article →

Meitnerium is a man-made chemical element. It is not found naturally in our world. Scientists must create it inside a laboratory. It has the symbol Mt and the atomic number 109. This element is part of the d-block of the periodic table. It is also a transactinide element.

Lise Meitner (1878-1968), lecturing at Catholic University, Washington, D.C., 1946
Lise Meitner (1878-1968), lecturing at Catholic University, Washington, D.C., 1946

This element is extremely radioactive and unstable. It breaks apart very quickly through things like alpha decay. Scientists study different versions of it called isotopes. The most stable version is meitnerium-278. It has a half-life of only 4.5 seconds. This means it lasts for a very short time. An unconfirmed version called meitnerium-282 might last 67 seconds.

Bohrium hassium meitnerium ceremony
Bohrium hassium meitnerium ceremony

A research team first made meitnerium in August 1982. They worked at the GSI Helmholtz Centre for Heavy Ion Research. This center is near Darmstadt, Germany. The team was led by Peter Armbruster and Gottfried Münzenberg. They hit a target of bismuth-209 with iron-58 nuclei. This process created a single atom of meitnerium-266. Another team confirmed this work three years later in the Soviet Union.

Bohrium hassium meitnerium ceremony
Bohrium hassium meitnerium ceremony

The name meitnerium was chosen to honor Lise Meitner. She was an Austrian-Swedish nuclear physicist. She helped discover nuclear fission. The GSI team suggested her name in September 1992. The name was officially adopted in 1997. It is the only element named after a woman who was not a myth.

Lise Meitner (1878-1968), lecturing at Catholic University, Washington, D.C., 1946
Lise Meitner (1878-1968), lecturing at Catholic University, Washington, D.C., 1946

Scientists believe meitnerium is a heavy metal. It should behave like its neighbors cobalt, rhodium, and iridium. It might be a noble metal. It is expected to be a solid under normal conditions. It would also have a very high density. No one has measured its actual chemistry yet. This is because it is very hard and expensive to produce.

Bohrium hassium meitnerium ceremony
Bohrium hassium meitnerium ceremony
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File:Lise Meitner (1878-1968), lecturing at Catholic University, Washington, D.C., 1946.jpg
Lise Meitner (1878-1968), lecturing at...
File:Bohrium hassium meitnerium ceremony.jpg
Bohrium hassium meitnerium ceremony.jpg
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