Cerium essays

Cerium essays Cerium is in the sixth period of the periodic table. Its atomic number is fifty-eight, which means it has fifty-eight protons and electrons. It has an atomic mass of 140.12, giving it eighty-two neutrons. Cerium is a soft, iron gray metal of the rare earth group of chemical elements, also called the lanthanide series. Its also a solid. Cerium was discovered in 1803 by Swedish chemist Jons Berzelius and geoligist Whilhelm Von Hisinger, and independently by German chemist Martin Klaproth. It was named for the asteroid Ceres, which was discovered in 1801. Pure cerium was prepared and produced in 1875 by Hillerbrand and Norton. Cerium is a natural element, opposed to synthetic, or man made. It is found in many minerals and is obtained commercially from the minerals, monazite, or phosphorus, and bastnasite. It has thirty known isotopes. Radioactive isotopes of cerium occur during the fission of uranium, thorium, and plutonium. Its electron structure is very easily changed. Cerium has many unique properties. For instance, each of the lanthanide elements has a common valance of positive three, however cerium is an exception in that it can have a valance of positive four. The higher oxidation state is useful for separating cerium from the other rare-earth elements and also makes it possible for cerium to form very strong oxidizing agents. It is also added to alloys to make them stronger and is used in self-cleaning ovens, and other heat resistant alloys. It has a melting point of 1463 degrees farenheight, and a boiling point of 5894.6 degrees farenheight. It is a metal that may ignite if scratched with a file. The metal readily oxidizes in moist air at room temperature. Cerium compounds may be observed with the emission spectrometer. It has a cubic crystal structure. Cerium has six energy levels. ...