Niobium

Khairi Marsh 11/10/09 Element Lab  __**Niobium**__ __**Symbol**__: Nb __**Atomic Number**:__ 41 __**Protons**:__ 41
 * Electrons**: 41[[image:nio2.jpg]]
 * Neutrons**: 52
 * Most Common Isotopes**:
 * ** Isotope ** || ** Half Life ** ||
 * Nb-90 || 14.6 hours ||
 * Nb-91 || 700.0 years ||
 * Nb-91m || 62.0 days ||
 * Nb-92 || 3.6E7 years ||
 * Nb-92m || 10.13 days ||
 * Nb-93 || Stable ||
 * Nb-93m || 16.1 years ||
 * Nb-94 || 20000.0 years ||
 * Nb-94m || 6.26 minutes ||
 * Nb-95 || 34.97 days ||
 * Nb-95m || 3.61 days ||
 * Nb-96 || 23.4 hours ||
 * Nb-97 || 1.23 hours ||
 * Nb-97m || 58.1 seconds ||
 * Electron Configuration**:[[image:nio3.jpg]]

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 __5s1 4d4__


 * Physical and Chemical Properties**:

Niobium is a shiny gray metal with a melting point of 2,468°C (4,474°F) and a boiling point of 4,927°C (8,901°F). Its density is 8.57 grams per cubic centimeter. Niobium metal is resistant to attack by most common chemicals. It does not combine with **oxygen** or most other active elements except at high temperatures. It does not react with most strong acids unless they are hot and concentrated. **Effects of Niobium**:

Niobium and its compounds may be toxic; niobium dust causes eye and skin irritation. There have been no reports of human being poisoned by it. Apart from measuring its concentration, no research on niobium in humans has been undertaken. Niobium, when inhaled, is retained mainly in the lungs, and secondarily in bones. It interferes with calcium as an activator of enzyme systems. In laboratory animals, inhalation of niobium nitride or pentoxide can lead to scarring of the lungs at exposure levels of 40 mg/m3.


 * History**:

Niobium was discovered by the English chemist Charles Hatchett in 1801. He found a new element in a mineral sample that had been sent to England from Massachusetts, U.S in 1734 by a john Winthrop. The name of this mineral was called columbite and the new element columbium. This was named after Columbia, the poetical name for America. Columbium discovered by Hatchett, which was a probable mixture of the new element with tantalum.

Niobium metal has a number of important uses. It is a component of some stainless steels and also alloys with nonferrous metals. These alloys have good strength and other properties, and are used in pipeline construction. Niobium is hypoallergenic which benefits its use in jewelry.
 * Uses**:

[|www.webelements.com/]**niobium**/ en.wikipedia.org/wiki/**Niobium** www.lenntech.com/periodic/elements/nb.htm []
 * Sources**

.