Devoir de Philosophie

Nobelium - chemistry.

Publié le 11/05/2013

Extrait du document

Nobelium - chemistry. Nobelium, symbol No, radioactive metallic element with an atomic number of 102. Nobelium is one of the transuranium elements in the actinide series of the periodic table (see Periodic Law). The element is named for the Swedish inventor and philanthropist Alfred Bernhard Nobel. Nobelium is not found in nature but is produced artificially in the laboratory. Separate discovery of the element was first claimed in 1957 by scientific groups in the United States, Britain, and Sweden, but the first confirmed discovery of a nobelium isotope, by a team of scientists at the Lawrence Berkeley National Laboratory in Berkeley, California, took place in 1958. The isotope was created by bombarding curium isotopes with carbon ions. Chemically, the properties of nobelium are unknown, but because it is an actinide, its properties should somewhat resemble those of the rare earth elements. Several isotopes are now known. The most stable isotope, nobelium-259, has a half-life of 58 minutes. See also Radioactivity. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

Liens utiles