transition metal - Article Index

Encyclopedia - Ammonia: Encyclopedia - Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula NH3. At standard temperature and pressure ammonia is a gas. It is toxic a...   » Read the article

Encyclopedia - Ceramics: Encyclopedia - Ceramics
The word ceramic is derived from the Greek word κεραμικος (keramikos, "having to do with pottery"). The term covers inorganic no...   » Read the article

Encyclopedia - Cadmium: Encyclopedia - Cadmium
Cadmium is a chemical element in the periodic table that has the symbol Cd and atomic number 48. A relatively rare, soft, bluish-white, t...   » Read the article

Encyclopedia - Zirconium: Encyclopedia - Zirconium
Zirconium is a chemical element in the periodic table that has the symbol Zr and atomic number 40. A lustrous gray-white, strong transiti...   » Read the article

Encyclopedia - Chromophore: Encyclopedia - Chromophore
A chromophore is the part (or moiety) of a molecule responsible for its color. This is a region in a molecule where the energy difference...   » Read the article

Encyclopedia - Yttrium: Encyclopedia - Yttrium
Yttrium is a chemical element in the periodic table that has the symbol Y and atomic number 39. A silvery metallic transition metal, yttr...   » Read the article

Encyclopedia - Coordinate Covalent Bond: Encyclopedia - Coordinate Covalent Bond
A coordinate covalent bond (also known as dative covalent bond) is a special type of covalent bond in which the shared electrons come fro...   » Read the article

Encyclopedia - Alfred Werner: Encyclopedia - Alfred Werner
Alfred Werner (December 12, 1866 - November 15, 1919) was a German Nobel prize-winning chemist. He won the Nobel Prize in Chemistry in 19...   » Read the article

Encyclopedia - Gold: Encyclopedia - Gold
Gold is a chemical element in the periodic table that has the symbol Au (L. aurum) and atomic number 79. A soft, shiny, yellow, dense, ma...   » Read the article

Encyclopedia - Silver: Encyclopedia - Silver
Silver is a chemical element with the symbol Ag (from the traditional abbreviation for the Latin argentum). A soft white lustrous transit...   » Read the article

Encyclopedia - Niobium: Encyclopedia Ii - Niobium - Applications
Niobium has a number of uses: it is a component of some stainless steels and an alloy of other nonferrous metals. These alloys are strong...   » Read the article

Encyclopedia - Molybdenum: Encyclopedia Ii - Molybdenum - Biological Role
Molybdenum has been found to have a role in the biology of all classes of organisms. It is found in two groups of enzymes, the nitrogenas...   » Read the article

Encyclopedia - Osmium: Encyclopedia Ii - Osmium - Notable Characteristics
Osmium in a metallic form is extremely dense, blue white, brittle and lustrous even at high temperatures, but proves to be extremely diff...   » Read the article

Encyclopedia - Zirconium: Encyclopedia Ii - Zirconium - History
Zirconium (Arabic zarkûn from Persian zargûn meaning "gold like") was discovered in 1789 by Martin Heinrich Klaproth and isolated in 18...   » Read the article

Encyclopedia - Platinum: Encyclopedia Ii - Platinum - Notable Characteristics
The metal appears silvery-white when pure, and firm. The metal is corrosion-resistant. The catalytic properties of the six platinum famil...   » Read the article

Encyclopedia - Phosphor: Encyclopedia Ii - Phosphor - Materials
Phosphors are usually made from a suitable host material, to which an activator is added. The best known type is a copper-activated zinc ...   » Read the article

Encyclopedia - Palladium: Encyclopedia Ii - Palladium - Notable Characteristics
Palladium is a soft steel-white metal that resembles platinum, doesn't tarnish in air, and is the least dense and has the lowest melting ...   » Read the article

Encyclopedia - Tungsten: Encyclopedia Ii - Tungsten - Applications
Tungsten is a metal with a wide range of uses, the largest of which is as tungsten carbide (W2C, WC) in cemented carbides. Cemented carbi...   » Read the article

Encyclopedia - Technetium: Encyclopedia Ii - Technetium - Occurrence And Production
Since technetium is unstable, only minute traces occur naturally in the Earth's crust as a spontaneous fission product of uranium. In 199...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - History
Mercury was known to the ancient Chinese and Hindus and was found in Egyptian tombs that date from 1500 BC In China, India and Tibet, mer...   » Read the article

Encyclopedia - Hubbard Model: Encyclopedia Ii - Hubbard Model - Example: 1d Chain Of Hydrogen Atoms
The hydrogen atom has only one electron, in the so-called s orbital, which can either be spin up () or spin down (). This orbital can be ...   » Read the article

Encyclopedia - Hafnium: Encyclopedia Ii - Hafnium - Notable Characteristics
This is a shiny silvery, ductile metal that is corrosion resistant and chemically similar to zirconium. The properties of hafnium are mar...   » Read the article

Encyclopedia - Lutetium: Encyclopedia Ii - Lutetium - Notable Characteristics And Applications
Lutetium is a silvery white corrosion-resistant trivalent metal that is relatively stable in air and is the heaviest and hardest of the r...   » Read the article

Encyclopedia - Rhenium: Encyclopedia Ii - Rhenium - Notable Characteristics
Rhenium is a silvery white metal, lustrous, and has one of the highest melting points of all elements, exceeded by only tungsten and carb...   » Read the article

Encyclopedia - Ceramic: Encyclopedia Ii - Ceramic - Properties Of Ceramics
Ceramic - Mechanical properties. Ceramic materials are usually ionic or covalently-bonded materials, and can be crystalline or amorphou...   » Read the article

Encyclopedia - Terpyridine: Encyclopedia Ii - Terpyridine - Synthesis
Terpyridine was synthesized from the oxidative coupling of pyridines at first. This method, however, has low-yield reactions and other ol...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - History
Mercury was known to the ancient Chinese and Hindus and was found in Egyptian tombs that date from 1500 BCE. In China, India and Tibet, m...   » Read the article

Encyclopedia - Electron Spin Resonance: Encyclopedia Ii - Electron Spin Resonance - Epr Theory
Electron spin resonance - Units and constants. A magnetic Field is described by some constants and units: Magnetic induction in tesla...   » Read the article

Encyclopedia - Sulfide: Encyclopedia Ii - Sulfide - Safety
Many metal sulfides are so insoluble that they are probably not very toxic. Some metal sulfides, when exposed to a strong mineral acid - ...   » Read the article

Encyclopedia - Tantalum: Encyclopedia Ii - Tantalum - Applications
The major use for tantalum, as tantalum metal powder, is in the production of electronic components, mainly tantalum capacitors. Tantalum...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - History
Mercury was known to the ancient Chinese and Hindus and was found in Egyptian tombs that date from 1500 BCE. In China, India and Tibet, m...   » Read the article

Encyclopedia - Rhodium: Encyclopedia Ii - Rhodium - Occurrence
The industrial extraction of rhodium is complex as the metal occurs in ores mixed with other metals such as palladium, silver, platinum, ...   » Read the article

Encyclopedia - Roentgenium: Encyclopedia Ii - Roentgenium - History
It was first created at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany on December 8, 1994. Only three atoms of i...   » Read the article

Encyclopedia - Carbene: Encyclopedia Ii - Carbene - Generation Of Carbenes
Most commonly, photolytic, thermal, or transition metal catalyzed decomposition of diazoalkanes is used to create carbene molecules. A va...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - Notable Characteristics
A polyvalent hard white metal, ruthenium is a member of the platinum group, has four crystal modifications and does not tarnish at normal...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - Notable Characteristics
Titanium is well known for its excellent corrosion resistance (almost as resistant as platinum), being able to withstand attack by acids,...   » Read the article

Encyclopedia - Yttrium: Encyclopedia Ii - Yttrium - Applications
Yttrium(III) oxide is the most important yttrium compound and is widely used to make YVO4 europium and Y2O3 europium phosphors that give ...   » Read the article

Encyclopedia - Ammonia: Encyclopedia Ii - Ammonia - Properties
Ammonia is a colourless gas with a characteristic pungent smell; it is lighter than air, its density being 0.589 times that of air. It is...   » Read the article

Encyclopedia - Iridium: Encyclopedia Ii - Iridium - Notable Characteristics
A platinum family metal, iridium is white, resembling platinum, but with a slight yellowish cast. Due to its extreme hardness and brittle...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Notable Characteristics
Gold is a metallic element with a characteristic yellow color, but can also be black or ruby when finely divided, while colloidal solutio...   » Read the article

Encyclopedia - Ceramics: Encyclopedia Ii - Ceramics - Properties Of Ceramics
Ceramics - Mechanical properties. Ceramic materials are usually ionic or covalently-bonded materials, and can be crystalline or amorpho...   » Read the article

Encyclopedia - Lawrencium: Encyclopedia Ii - Lawrencium - Notable Characteristics
The appearance of this element is unknown, however it is most likely silvery-white or gray and metallic. If sufficient amounts of lawrenc...   » Read the article

Encyclopedia - Silver: Encyclopedia Ii - Silver - Notable Characteristics
Silver is a very ductile and malleable (slightly harder than gold) univalent coinage metal with a brilliant white metallic luster that ca...   » Read the article

Encyclopedia - Cadmium: Encyclopedia Ii - Cadmium - Isotopes
Naturally occurring cadmium is composed of 8 isotopes. For two of them, natural radioactivity was observed, and other three are predicted...   » Read the article

Encyclopedia - Hydrodesulfurization: Encyclopedia Ii - Hydrodesulfurization - Process
In these hydrodesulfurization processes the liquid is treated with hydrogen gas using a molybdenum disulfide catylist which is oftein pro...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - Isotopes
Naturally occurring ruthenium is composed of seven isotopes. The most stable radioisotopes are Ru-106 with a half-life of 373.59 days, Ru...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - Organometallic Chemistry
It is quite easy to form compounds with carbon ruthenium bonds, these compounds tend to be darker and react more quickly than the osmium ...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - Applications
Mercury is used primarily for the manufacture of industrial chemicals or for electrical and electronic applications. It is used in some t...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - Compounds
The most important salts are: Mercury(I) chloride (AKA calomel) is sometimes still used in medicine and acousto-optical filters Mercury(...   » Read the article

Encyclopedia - Electron Spin Resonance: Encyclopedia Ii - Electron Spin Resonance - Epr Spectral Parameters
Electron spin resonance - The g factor. Knowledge of the g factor gives us information about the paramagnetic center's electronic struc...   » Read the article

Encyclopedia - Ceramics: Encyclopedia Ii - Ceramics - Classifications Of Technical Ceramics
Technical Ceramics can also be classified into three distinct material categories: Oxides: Alumina, zirconia Non-oxides: Carbides, borid...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - History
Ruthenium (Latin Ruthenia meaning "Russia") was discovered and isolated by Karl Klaus in 1844. Klaus showed that ruthenium oxide containe...   » Read the article

Encyclopedia - Ammonia: Encyclopedia Ii - Ammonia - Production
Because of its many uses, ammonia is one of the most highly-produced inorganic chemicals. Before the start of WWI most ammonia was obtain...   » Read the article

Encyclopedia - Rhodium: Encyclopedia Ii - Rhodium - History
Rhodium (Greek rhodon meaning "rose") was discovered in 1803 by William Hyde Wollaston soon after his discovery of palladium. Wollaston m...   » Read the article

Encyclopedia - Tantalum: Encyclopedia Ii - Tantalum - Isotopes
Natural tantalum consists of two isotopes. Ta-181 is a stable isotope, and Ta-180m, which has a half life of over 1015 years (see scienti...   » Read the article

Encyclopedia - Tantalum: Encyclopedia Ii - Tantalum - Occurrence
Tantalum occurs principally in the mineral tantalite [(Fe, Mn) Ta2O6] and euxenite (other minerals: samarskite, and fergusonite). Tantalu...   » Read the article

Encyclopedia - Tantalum: Encyclopedia Ii - Tantalum - History
Tantalum (Greek Tantalus, mythological character) was discovered in Sweden in 1802 by Anders Ekeberg and isolated in 1820 by Jöns Berzel...   » Read the article

Encyclopedia - Ammonia: Encyclopedia Ii - Ammonia - History
Salts of ammonia have been known from very early times; thus the term Hammoniacus sal appears in the writings of Pliny, although it is no...   » Read the article

Encyclopedia - Rhodium: Encyclopedia Ii - Rhodium - Isotopes
Naturally occurring rhodium is composed of only one isotope (Rh-103). The most stable radioisotopes are Rh-101 with a half-life of 3.3 ye...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - Occurrence In The Environment
Abundance Crustal ~7×10-2 mg/kg Oceans ~3×10-5 mg/L Preindustrial deposition rates of mercury from the atmosphere may be in the range...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - Applications
Due to its highly effective ability to harden platinum and palladium, ruthenium is used in Pt and Pd alloys to make severe wear resistanc...   » Read the article

Encyclopedia - Ceramics: Encyclopedia Ii - Ceramics - Processing Of Ceramic Materials
Non-crystalline ceramics, being glasses, tend to be formed from melts. The glass is shaped when either fully molten, by casting, or when ...   » Read the article

Encyclopedia - Ceramics: Encyclopedia Ii - Ceramics - Other Applications Of Ceramics
A couple of decades ago, Toyota researched production of an adiabatic ceramic engine which can run at a temperature of over 6000 °F (330...   » Read the article

Encyclopedia - Ruthenium: Encyclopedia Ii - Ruthenium - Occurrence
This element is generally found in ores with the other platinum group metals in the Ural Mountains and in North and South America. Small ...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Occurrence
Due to its relative chemical inertness gold is usually found as the native metal or alloy. Occasionally large accumulations of native gol...   » Read the article

Encyclopedia - Rhenium: Encyclopedia Ii - Rhenium - History
Rhenium (Latin Rhenus meaning "Rhine") was the last naturally-occurring element to be discovered. The existence of an as-yet undiscovered...   » Read the article

Encyclopedia - Silver: Encyclopedia Ii - Silver - Occurrence
Silver is found in native form, combined with sulfur, arsenic, antimony, or chlorine and in various ores such as argentite (Ag2S) and hor...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - Compounds
The most important salts are: Mercury(I) chloride (AKA calomel) is sometimes still used in medicine and acousto-optical filters Mercury(...   » Read the article

Encyclopedia - Lutetium: Encyclopedia Ii - Lutetium - Isotopes
Naturally occurring lutetium is composed of 1 stable isotope Lu-175 (97.41% natural abundance). 33 radioisotopes have been characterized,...   » Read the article

Encyclopedia - Silver: Encyclopedia Ii - Silver - History
Silver (from Anglo-Saxon seolfor, compare Old High German silabar; Ag is from the Latin argentum) has been known since ancient times. It ...   » Read the article

Encyclopedia - Terpyridine: Encyclopedia Ii - Terpyridine - Properties
Terpyridine is a tridentate ligand and forms a complex with a transition metal ion in the same way as other polypyridine compounds, such ...   » Read the article

Encyclopedia - Ceramic: Encyclopedia Ii - Ceramic - Other Applications Of Ceramics
A couple of decades ago, Toyota researched production of an adiabatic ceramic engine which can run at a temperature of over 6000 °F (330...   » Read the article

Encyclopedia - Ceramic: Encyclopedia Ii - Ceramic - Processing Of Ceramic Materials
Non-crystalline ceramics, being glasses, tend to be formed from melts. The glass is shaped when either fully molten, by casting, or when ...   » Read the article

Encyclopedia - Ceramic: Encyclopedia Ii - Ceramic - Classifications Of Technical Ceramics
Technical Ceramics can also be classified into three distinct material categories: Oxides: Alumina, zirconia Non-oxides: Carbides, borid...   » Read the article

Encyclopedia - Lutetium: Encyclopedia Ii - Lutetium - Occurrence
Found with almost all other rare-earth metals but never by itself, lutetium is very difficult to separate from other elements and is the ...   » Read the article

Encyclopedia - Lutetium: Encyclopedia Ii - Lutetium - History
Lutetium (Latin Lutetia meaning Paris) was independently discovered in 1907 by French scientist Georges Urbain and Austrian mineralogist ...   » Read the article

Encyclopedia - Cadmium: Encyclopedia Ii - Cadmium - History
Cadmium (Latin cadmia, Greek kadmeia meaning "calamine") was discovered in Germany in 1817 by Friedrich Strohmeyer. Strohmeyer found the ...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Symbolism
Gold has been associated with the extremities of utmost evil and great sanctity throughout history. The Golden Calf is a widely-recognise...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Production
Economic gold extraction can be achieved from ore grades as little as 0.5 g/1000 kg (0.5 ppm) on average in large easily mined deposits, ...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Gold And The Money Supply
In January 1959 US M3 money supply was $288.8 billion, and the official gold holdings of the United States was then 17,335.1 tonnes, or a...   » Read the article

Encyclopedia - Hafnium: Encyclopedia Ii - Hafnium - History
Hafnium (Latin Hafnia for "Copenhagen", the home town of Niels Bohr) was discovered by Dirk Coster and Georg von Hevesy in 1923 in Copenh...   » Read the article

Encyclopedia - Cadmium: Encyclopedia Ii - Cadmium - Notable Characteristics
Cadmium is a soft, malleable, ductile, bluish-white bivalent metal which can be easily cut with a knife. It is similar in many respects t...   » Read the article

Encyclopedia - Silver: Encyclopedia Ii - Silver - Isotopes
Naturally occurring silver is composed of the two stable isotopes Ag-107 and Ag-109 with Ag-107 being the more abundant (51.839% natural ...   » Read the article

Encyclopedia - Silver: Encyclopedia Ii - Silver - Precautions And Health Effects
Silver plays no known natural biological role in humans, and possible health effects of silver are a subject of dispute. Silver itself is...   » Read the article

Encyclopedia - Hubbard Model: Encyclopedia Ii - Hubbard Model - More Complex Systems
Although the Hubbard model is useful in describing systems such as a 1-D chain of hydrogen atoms, it is important to note that in more co...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - History
Gold ( Sanskrit jval, Greek χρυσóς [khrisós], Latin aurum for "shining dawn", Anglo-Saxon gold, Chinese 金 [jīn],Japanese 金 [k...   » Read the article

Encyclopedia - Ammonia: Encyclopedia Ii - Ammonia - Uses
The most important single use of ammonia is in the production of nitric acid. A mixture of one part ammonia to nine parts air is passed o...   » Read the article

Encyclopedia - Platinum: Encyclopedia Ii - Platinum - Occurrence
Platinum is often found as native platinum and alloyed with iridium as platiniridium. The platinum arsenide, sperrylite, is a major sourc...   » Read the article

Encyclopedia - Platinum: Encyclopedia Ii - Platinum - History
Naturally-occurring platinum and platinum-rich alloys have been known for a long time. Though the metal was used by pre-Columbian Native ...   » Read the article

Encyclopedia - Palladium: Encyclopedia Ii - Palladium - Occurrence
Palladium is found as a free metal and alloyed with platinum and gold with platinum group metals in placer deposits of the Ural Mountains...   » Read the article

Encyclopedia - Palladium: Encyclopedia Ii - Palladium - History
Palladium was discovered by William Hyde Wollaston in 1803. This element was named by Wollaston in 1804 after the asteroid Pallas, which ...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Symbolism
Gold has been associated with the extremities of utmost evil and great sanctity throughout history. The Golden Calf is a widely-recognise...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Gold In Investment Portfolios
As a tangible investment gold is sometimes held as part of a portfolio because over the long term gold has an extensive history of mainta...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Occurrence
Due to its relative chemical inertness gold is usually found as the native metal or alloy. Occasionally large accumulations of native gol...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Production
Economic gold extraction can be achieved from ore grades as little as 0.5 g/1000 kg (0.5 ppm) on average in large easily mined deposits, ...   » Read the article

Encyclopedia - Gold: Encyclopedia Ii - Gold - Compounds/isotopes
Although gold is a noble metal, it can form many compounds, auric chloride (AuCl3) and chlorauric acid (HAuCl4) being the most common. Go...   » Read the article

Encyclopedia - Palladium: Encyclopedia Ii - Palladium - Applications
When it is finely divided, palladium forms a good catalyst and is used to speed up hydrogenation and dehydrogenation reactions, as well a...   » Read the article

Encyclopedia - Iridium: Encyclopedia Ii - Iridium - Applications
The principal use of iridium is as a hardening agent in platinum alloys. Other uses: For making crucibles and devices that require high ...   » Read the article

Encyclopedia - Molybdenum: Encyclopedia Ii - Molybdenum - Precautions
Molybdenum dusts and molybdenum compounds, such as molybdenum trioxide and water-soluble molybdates, may have slight toxicities if inhale...   » Read the article

Encyclopedia - Molybdenum: Encyclopedia Ii - Molybdenum - Occurrence
Though molybdenum is found in such minerals as wulfenite (PbMoO4) or powellite (CaMoO4), the main commercial source of molybdenum is moly...   » Read the article

Encyclopedia - Mercury Element: Encyclopedia Ii - Mercury Element - Occurrence In The Environment
Abundance Crustal ~7×10-2 mg/kg Oceans ~3×10-5 mg/L Preindustrial deposition rates of mercury from the atmosphere may be in the range...   » Read the article