HOME TheInfoList.com
Providing Lists of Related Topics to Help You Find Great Stuff

picture info

Chromium
Chromium
Chromium
is a chemical element with symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard and brittle metal[4] which takes a high polish, resists tarnishing, and has a high melting point. The name of the element is derived from the Greek word χρῶμα, chrōma, meaning color,[5] because many chromium compounds are intensely colored. Ferrochromium
Ferrochromium
alloy is commercially produced from chromite by silicothermic or aluminothermic reactions and chromium metal by roasting and leaching processes followed by reduction with carbon and then aluminium. Chromium
Chromium
metal is of high value for its high corrosion resistance and hardness
[...More...]

picture info

Standard Atomic Weight
The standard atomic weight (Ar, standard, a relative atomic mass) is the atomic weight (Ar) of a chemical element, as appearing and met in the earthly environment. It reflects the variance of natural isotopes (and so weight differences) of an element. Values are defined by (restricted to) the IUPAC
IUPAC
(CIAAW) definition of natural, stable, terrestridal sources. It is the most common and practical atomic weight used, for example to determine molar mass. The specified definition is to use many representative sources (samples) from the Earth, so that the value can widely be used as 'the' atomic weight for real life substances—for example, in pharmaceuticals and scientific research
[...More...]

picture info

Indium
Indium
Indium
is a chemical element with symbol In and atomic number 49. It is a post-transition metal that makes up 0.21 parts per million of the Earth's crust. Very soft and malleable, indium has a melting point higher than sodium and gallium, but lower than lithium and tin. Chemically, indium is similar to gallium and thallium, and it is largely intermediate between the two in terms of its properties.[6] Indium
Indium
was discovered in 1863 by Ferdinand Reich
Ferdinand Reich
and Hieronymous Theodor Richter by spectroscopic methods. They named it for the indigo blue line in its spectrum. Indium
Indium
was isolated the next year. Indium
Indium
is a minor component in zinc sulfide ores and is produced as a byproduct of zinc refinement
[...More...]

picture info

Arsenic
Arsenic
Arsenic
is a chemical element with symbol As and atomic number 33. Arsenic
Arsenic
occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic
Arsenic
is a metalloid. It has various allotropes, but only the gray form is important to industry. The primary use of metallic arsenic is in alloys of lead (for example, in car batteries and ammunition). Arsenic
Arsenic
is a common n-type dopant in semiconductor electronic devices, and the optoelectronic compound gallium arsenide is the second most commonly used semiconductor after doped silicon. Arsenic
Arsenic
and its compounds, especially the trioxide, are used in the production of pesticides, treated wood products, herbicides, and insecticides
[...More...]

picture info

Palladium
Palladium
Palladium
is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust (hydrocarbons, carbon monoxide, and nitrogen dioxide) into less noxious substances (nitrogen, carbon dioxide and water vapor)
[...More...]

picture info

Titanium
Titanium
Titanium
is a chemical element with symbol Ti and atomic number 22. It is a lustrous transition metal with a silver color, low density, and high strength. Titanium
Titanium
is resistant to corrosion in sea water, aqua regia, and chlorine. Titanium
Titanium
was discovered in Cornwall, Great Britain, by William Gregor in 1791, and was named by Martin Heinrich Klaproth
Martin Heinrich Klaproth
after the Titans of Greek mythology. The element occurs within a number of mineral deposits, principally rutile and ilmenite, which are widely distributed in the Earth's crust
Earth's crust
and lithosphere, and it is found in almost all living things, water bodies, rocks, and soils.[5] The metal is extracted from its principal mineral ores by the Kroll[6] and Hunter processes
[...More...]

picture info

Silver
Silver
Silver
is a chemical element with symbol Ag (from the Latin
Latin
argentum, derived from the Proto-Indo-European
Proto-Indo-European
h₂erǵ: "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining. Silver
Silver
has long been valued as a precious metal
[...More...]

picture info

Gallium
Gallium
Gallium
is a chemical element with symbol Ga and atomic number 31. It is in group 13 of the periodic table, and thus has similarities to the other metals of the group, aluminium, indium, and thallium. Gallium
Gallium
does not occur as a free element in nature, but as gallium(III) compounds in trace amounts in zinc ores and in bauxite.[5] Elemental gallium is a soft, silvery blue metal at standard temperature and pressure, a brittle solid at low temperatures, and a liquid at temperatures greater than 29.76 °C (85.57 °F) (above room temperature, but below the normal human body temperature). The melting point of gallium is used as a temperature reference point. Gallium
Gallium
alloys are used in thermometers as a non-toxic and environmentally friendly alternative to mercury, and can withstand higher temperatures than mercury
[...More...]

picture info

Germanium
Germanium
Germanium
is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Pure germanium is a semiconductor with an appearance similar to elemental silicon. Like silicon, germanium naturally reacts and forms complexes with oxygen in nature. Because it seldom appears in high concentration, germanium was discovered comparatively late in the history of chemistry. Germanium ranks near fiftieth in relative abundance of the elements in the Earth's crust. In 1869, Dmitri Mendeleev
Dmitri Mendeleev
predicted its existence and some of its properties from its position on his periodic table, and called the element ekasilicon. Nearly two decades later, in 1886, Clemens Winkler
Clemens Winkler
found the new element along with silver and sulfur, in a rare mineral called argyrodite
[...More...]

picture info

Selenium
Selenium
Selenium
is a chemical element with symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium
Selenium
(from Ancient Greek
Ancient Greek
σελήνη (selḗnē) "Moon") was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium
Selenium
is found in metal sulfide ores, where it partially replaces the sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Minerals that are pure selenide or selenate compounds are known but rare
[...More...]

picture info

Chlorine
Chlorine
Chlorine
is a chemical element with symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine
Chlorine
is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity, behind only oxygen and fluorine. The most common compound of chlorine, sodium chloride (common salt), has been known since ancient times. Around 1630, chlorine gas was first synthesised in a chemical reaction, but not recognised as a fundamentally important substance. Carl Wilhelm Scheele
Carl Wilhelm Scheele
wrote a description of chlorine gas in 1774, supposing it to be an oxide of a new element
[...More...]

picture info

Krypton
Krypton
Krypton
(from Ancient Greek: κρυπτός, translit. kryptos "the hidden one") is a chemical element with symbol Kr and atomic number 36. It is a member of group 18 (noble gases) elements. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. With rare exceptions, krypton is chemically inert. Krypton, like the other noble gases, is used in lighting and photography. Krypton
Krypton
light has many spectral lines, and krypton plasma is useful in bright, high-powered gas lasers (krypton ion and excimer lasers), each of which resonates and amplifies a single spectral line. Krypton
Krypton
fluoride also makes a useful laser
[...More...]

picture info

Rubidium
Rubidium
Rubidium
is a chemical element with symbol Rb and atomic number 37. Rubidium
Rubidium
is a soft, silvery-white metallic element of the alkali metal group, with a standard atomic weight of 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other alkali metals, including rapid oxidation in air. On Earth, natural rubidium comprises two isotopes: 72% is the stable isotope, 85Rb; 28% is the slightly radioactive 87Rb, with a half-life of 49 billion years—more than three times longer than the estimated age of the universe. German chemists Robert Bunsen
Robert Bunsen
and Gustav Kirchhoff
Gustav Kirchhoff
discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. Rubidium's compounds have various chemical and electronic applications
[...More...]

picture info

Strontium
Strontium
Strontium
is the chemical element with symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white yellowish metallic element that is highly reactive chemically. The metal forms a dark oxide layer when it is exposed to air. Strontium
Strontium
has physical and chemical properties similar to those of its two vertical neighbors in the periodic table, calcium and barium. It occurs naturally mainly in the minerals celestine, strontianite and is mined mostly from the first two of these
[...More...]

picture info

Zirconium
Zirconium
Zirconium
is a chemical element with symbol Zr and atomic number 40. The name zirconium is taken from the name of the mineral zircon, the most important source of zirconium. The word zircon comes from the Persian word zargun زرگون, meaning "gold-colored".[5] It is a lustrous, grey-white, strong transition metal that resembles hafnium and, to a lesser extent, titanium. Zirconium
Zirconium
is mainly used as a refractory and opacifier, although small amounts are used as an alloying agent for its strong resistance to corrosion. Zirconium
Zirconium
forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable
[...More...]

picture info

Technetium
Technetium
Technetium
is a chemical element with symbol Tc and atomic number 43. It is the lightest element whose isotopes are all radioactive; none are stable, excluding the fully ionized state of 97Tc.[4] Nearly all technetium is produced synthetically, and only about 18000 tons can be found at any given time in the Earth's crust. Naturally occurring technetium is a spontaneous fission product in uranium ore and thorium ore, the most common source, or the product of neutron capture in molybdenum ores. The chemical properties of this silvery gray, crystalline transition metal are intermediate between rhenium and manganese, which it lies between in group 7 of the periodic table. The most common naturally occuring isotope is 99Tc. Many of technetium's properties were predicted by Dmitri Mendeleev before the element was discovered. Mendeleev noted a gap in his periodic table and gave the undiscovered element the provisional name ekamanganese (Em)
[...More...]

.