It is more abundant than a few well-known metals like tungsten, antimony, and cadmium. OccurrenceĬaesium is found in small amounts, around 3 parts per million, in the Earth’s crust in the minerals pollucite, rhodizite, and lepidolite. Prior to this time, the element had no significant practical applications. Before the 1920s, it was primarily used in vacuum tubes as a “getter” to remove trace amounts of oxygen and other gasses that became trapped in the tube when it was sealed. It was not until later, when German chemist Carl Setterberg at the University of Bonn electrolyzed caesium cyanide CsCN, that pure caesium metal was successfully isolated.Ĭaesium has traditionally been used mostly in research and development. They attempted to create elemental caesium through the electrolysis of molten caesium chloride, but instead obtained a blue, homogeneous substance. Kirchhoff were the first to discover the element caesium through spectroscopic means, using the spectroscope they had just invented the year before. Gustav Kirchhoff (left) and Robert Bunsen | source: Science History Institute It is one of the elements with the most isotopes, with 40 known isotopes ranging from Caesium-112 to Caesium-151. With a Pauling scale value of 0.79, it is the least electronegative element. Due to its reactive nature, caesium is considered a hazardous material and must be stored and transported separately for safety reasons. This highly reactive silvery metal melts just above room temperature at 28.5 ℃ (83.3 ℉). It is a relatively rare element, with a total abundance in the Earth’s crust of about 3 parts per million.Ĭaesium reacts spontaneously in the air, which makes it hard to handle. In 1860, German chemist Robert Bunsen and physicist Gustav Kirchhoff discovered caesium using the newly invented method of flame spectroscopy. It is a soft, silvery-gold alkali metal whose name comes from the Latin word “caesius” (which means sky blue). Caesium (Cs), also spelled as cesium in American English, is a chemical element of the periodic table, located in group 1 and period 6, and has the atomic number 55. Data Series 140, Historical Statistics for Mineral and Material Commodities in the United States, Version 2011, USGS.HyperPhysics, Georgia State University, Abundance of Elements in Earth's Crust.World Book Encyclopedia, Exploring Earth.U data is pure element required for consumption by current reactor fleet Archived at the Wayback Machine. For many elements like Si, Al, data are ambiguous (many forms produced) and are taken for the pure element. Data for B, K, Ti, Y are given not for the pure element but for the most common oxide, data for Na and Cl are for NaCl. All production numbers are for mines, except for Al, Cd, Fe, Ge, In, N, Se (plants, refineries), S (all forms) and As, Br, Mg, Si (unspecified). ^ Commodity Statistics and Information.^ Abundance of elements in the earth’s crust and in the sea, CRC Handbook of Chemistry and Physics, 97th edition (2016–2017), p.^ "List of Periodic Table Elements Sorted by Abundance in Earth's crust".Archived from the original on 9 March 2007. Archived from the original on 10 April 2007. ^ David Kring, Composition of Earth's continental crust as inferred from the compositions of impact melt sheets, Lunar and Planetary Science XXVIII."Chemical Composition of the Mantle", Theory of the Earth, pp. Clarke number - lists of historical data and terminology.List of abundance by element Abundance of chemical elements in Earth's (continental) crust, according to various sources The abundance of elements in Earth's crust is shown in tabulated form with the estimated crustal abundance for each chemical element shown as mg/kg, or parts per million (ppm) by mass (10,000 ppm = 1%).Įstimates of elemental abundance are difficult because (a) the composition of the upper and lower crust are quite different, and (b) the composition of the continental crust can vary drastically by locality. Tellurium and selenium are concentrated as sulfides in the core and have also been depleted by preaccretional sorting in the nebula that caused them to form volatile hydrogen selenide and hydrogen telluride. These have been depleted by being relocated deeper into the Earth's core. ![]() The rarest elements in the crust (shown in yellow) are not the heaviest, but are rather the siderophile (iron-loving) elements in the Goldschmidt classification of elements. Abundance (atom fraction) of the chemical elements in Earth's upper continental crust as a function of atomic number.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |