Geiger,+Brian

Bunsen and Kirchoff Who discovered Cesium.  Cesium fountain atomic clock, serving as the US time and frenquency time, with an Uncertianly of 5.10×10−16 (as of 2005)

Type in the content of your page here. Cesium

__ What Is cesium used for ? __ Cesium-137 is one of the most common radioisotopes used in industry. Thousands of devices use cesium-137: · moisture-density gauges, widely used in the construction industry · leveling gauges, used in industries to detect liquid flow in pipes and tanks · thickness gauges, for measuring thickness of sheet metal, paper, film and many other products · well-logging devices in the drilling industry to help characterize rock strata Cesium-137 is also used in medical therapy to treat cancer.


 * __ History __**

==It was discovered in 1860 by Kirchhoff and Bunsen while examining the residues that were obtained by evaporation of mineral waters. The new bright lines in the blue region were attributed to a new element - given the name cesium for the Latin caesius - sky blue.Extraction of cesium compounds by bunseninvolved concentration of the cesium and other impurities by evaporation of large volumes of mineral water. Bunsen prepared chlorides, carbonates and other salts of cesium. He studied the properties of these salts and attempted to prepare cesium metal but was unsuccessful. The metal was first obtained by Setterburg in 1882 by electrolysis of a cesium cyanide-barium cyanide melt.Cesium had no significant industrial application until 1926 when the metal was used as a getter and an effective means for reducing the electron work function on coated Tungsten filaments in radio tubes.== __Atomic Number__ 55 __ Atomic Symbol __ C S __ Atomic Weight __ 132.9054 __Electron Configuration __<span style="color: #1f497d; font-family: Algerian; font-size: 24pt; line-height: 115%; mso-themecolor: text2;"> [X <span style="color: #1f497d; font-family: Algerian; font-size: 16pt; line-height: 115%; mso-bidi-font-size: 24.0pt; mso-themecolor: text2;">e <span style="color: #1f497d; font-family: Algerian; font-size: 24pt; line-height: 115%; mso-themecolor: text2;">]6 <span style="color: #1f497d; font-family: Algerian; font-size: 16pt; line-height: 115%; mso-bidi-font-size: 24.0pt; mso-themecolor: text2;">s <span style="color: #1f497d; font-family: Algerian; font-size: 24pt; line-height: 115%; mso-themecolor: text2; msospacerun: yes; msothemecolor: text2;"> __Atomic Radius__ 265.4pm __Melting Point__ 28.5 c __Boiling Point__ 671 C __Atomic Mass__ 132.90546 amu

__Crystal Structure__: Cubic __Density__ @ 293 K: 1.873 g/cm3 __Color of Cesium__ : silvery-white
<span style="color: #92d050; font-family: 'Arial Black','sans-serif'; font-size: 16pt; line-height: 115%; mso-ansi-language: EN;">Caesium is a soft, ductile, silvery-white metal which develops a silvery-gold hue in the presence of even trace amounts of oxygen. It has a melting point of 28.4 ° C, making it one of the few metals that are liquid near room temperature.
 * <span style="color: red; font-family: 'Arial Black','sans-serif'; font-size: 20pt; line-height: 115%;">Cesium is a Metal **

__Sources__ <span style="color: #00b0f0; font-family: Algerian; font-size: 22pt; line-height: 115%; mso-ansi-language: EN-US; mso-bidi-font-family: 'Times New Roman'; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">[|cesium] [|Periodic Table of elements] <span style="color: #00b0f0; font-family: Algerian; font-size: 22pt; line-height: 115%; mso-ansi-language: EN-US; mso-bidi-font-family: 'Times New Roman'; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin;">[|The Element Cesium]