Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Ore Genesis Processes
Evans (1993) divides ore genesis into the following main categories based on physical process. These are internal processes, hydrothermal...   » Read the article

Encyclopedia - Bromide Chemistry: Encyclopedia - Bromide Chemistry
Bromide chemistry - Definition. A bromide ion is an bromine atom with charge -1. Compounds with bromine in formal oxidation state -1 ar...   » Read the article

Encyclopedia - Beagle 2: Encyclopedia - Beagle 2
Beagle 2 was an unsuccessful British landing spacecraft that formed part of the European Space Agency's 2003 Mars Express mission. Beagle...   » Read the article

Encyclopedia - Acid Dissociation Constant: Encyclopedia - Acid Dissociation Constant
In chemistry and biochemistry, acid dissociation constant, the acidity constant, or the acid-ionization constant (Ka) is a specific type ...   » Read the article

Encyclopedia - Valence Chemistry: Encyclopedia - Valence Chemistry
In chemistry, valence is the power of an atom of an element to combine with other atoms measured by the number of electrons which an atom...   » 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 - Alkane: Encyclopedia - Alkane
An alkane in organic chemistry is a saturated hydrocarbon without cycles, that is, an acyclic hydrocarbon in which the molecule has the m...   » Read the article

Encyclopedia - Zinc: Encyclopedia - Zinc
Zinc (from German zink) is a chemical element in the periodic table that has the symbol Zn and atomic number 30. Zinc - Notable character...   » Read the article

Encyclopedia - Chromate: Encyclopedia - Chromate
Chromates and dichromates are salts of chromic acid and dichromic acid, respectively. Chromate salts contain the chromate ion, CrO42-, an...   » 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 - Goldiii Chloride: Encyclopedia - Goldiii Chloride
Gold(III) chloride, traditionally called auric chloride, is one of the most common compounds of gold. It has the formula AuCl3. The Roman...   » Read the article

Encyclopedia - Chlorate: Encyclopedia - Chlorate
The chlorate ion ClO3-. A chlorate (compound) is a compound that contains this group, with chlorine in oxidation state +5. Chlorate - Ex...   » 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 - Electron Counting: Encyclopedia Ii - Electron Counting - Examples Of The 18 Ve Rule
There are two different approaches one can use when counting electrons, each arriving at the same total. The constituents (i.e. metal and...   » Read the article

Encyclopedia - Chlorite: Encyclopedia Ii - Chlorite - Manufacture
The free acid, chlorous acid, HClO2, is only stable at low concentrations. Since it cannot be concentrated, it is not a commercial produc...   » Read the article

Encyclopedia - Fermium: Encyclopedia Ii - Fermium - History
Fermium (after Enrico Fermi) was first discovered by a team led by Albert Ghiorso in 1952. The team found fermium-255 in the debris of th...   » Read the article

Encyclopedia - Chlorate: Encyclopedia Ii - Chlorate - Definition
The chlorate ion ClO3-. A chlorate (compound) is a compound that contains this group, with chlorine in oxidation state +5. ... See also...   » Read the article

Encyclopedia - Nickel: Encyclopedia Ii - Nickel - Notable Characteristics
Nickel is a silvery white metal that takes on a high polish. It belongs to the iron group, and is hard, malleable, and ductile. It occurs...   » Read the article

Encyclopedia - Cluster Chemistry: Encyclopedia Ii - Cluster Chemistry - Metal Clusters
The oldest identified metal cluster is calomel which was known to the Indians in the 12th century. The existence of a mercury to mercury ...   » Read the article

Encyclopedia - Perchlorate: Encyclopedia Ii - Perchlorate - Perchlorate Pollution
Perchlorates are a neurotoxin. They have been found to affect the thyroid gland in particular. When perchlorates enter the body, they blo...   » Read the article

Encyclopedia - Potassium Permanganate: Encyclopedia Ii - Potassium Permanganate - Uses
Potassium permanganate is used as an oxidizing agent in many different kinds of chemical reactions in a laboratory and in industry. It is...   » 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 - 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 - 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 - Phosphorus Trichloride: Encyclopedia Ii - Phosphorus Trichloride - Chemical Properties
In phosphorus trichloride (PCl3), the phosphorus is in the +3 oxidation state and the chlorines are in the -1 oxidation state. PCl3 react...   » Read the article

Encyclopedia - Oxide: Encyclopedia Ii - Oxide - Current Naming
Oxides can be named after the amount of oxygen atoms in the oxide. Oxides containing only one oxygen are called oxide or monoxide, those ...   » 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 - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Extraction With Chemical Change
Liquid-liquid extraction - Solvation mechanism. Using solvent extraction it is possible to extract uranium, plutonium, or thorium from ...   » Read the article

Encyclopedia - Goldiii Chloride: Encyclopedia Ii - Goldiii Chloride - Uses
Gold(III) chloride is one of the most common gold compounds and it is therefore used as the starting point for the synthesis of many othe...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Molecular Geometry
The molecular structure of the alkanes directly affects their physical and chemical characteristics. It is derived from the electron conf...   » Read the article

Encyclopedia - Scandium: Encyclopedia Ii - Scandium - Applications
Approximately 20 kg (as Sc2O3) of scandium are used annually in the United States to make high-intensity lights. Scandium iodide added to...   » Read the article

Encyclopedia - Zinc: Encyclopedia Ii - Zinc - Applications
Zinc is the fourth most common metal in use, trailing only iron, aluminium, and copper in annual production. Zinc is used to galvanise m...   » Read the article

Encyclopedia - Zinc-carbon Battery: Encyclopedia Ii - Zinc-carbon Battery - Mechanism
The container of the dry cell, which also serves as one of the electrodes, is made of zinc. The container is lined with porous paper bag ...   » Read the article

Encyclopedia - Bromide Chemistry: Encyclopedia Ii - Bromide Chemistry - Definition
A bromide ion is an bromine atom with charge -1. Compounds with bromine in formal oxidation state -1 are called bromides. This can includ...   » 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 - Acid Dissociation Constant: Encyclopedia Ii - Acid Dissociation Constant - The Relative Strengths Of Acids And Bases
The strengths of acids and bases in aqueous solutions are determined by the values of the dissociation constants Ka and Kb for acids and ...   » Read the article

Encyclopedia - Beagle 2: Encyclopedia Ii - Beagle 2 - Background
Beagle 2 was conceived by a group of British academics headed by Professor Colin Pillinger of the Open University, in collaboration with ...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - Compounds
The +4 oxidation state dominates in titanium chemistry, but compounds in the +3 oxidation state are also common. Because of this high oxi...   » 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 - Alkane: Encyclopedia Ii - Alkane - Purification And Use
Alkanes are both important raw materials of the chemical industry and the most important fuels of the world economy. The starting materia...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Copper
Copper is found in association with many other metals and deposit styles. Commonly, copper is either formed within sedimentary rocks, or ...   » Read the article

Encyclopedia - Tungsten: Encyclopedia Ii - Tungsten - Compounds
The most common oxidation state of tungsten is +6, but it exhibits all oxidation states from +2 to +6. Tungsten typically combines with o...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Uranium
Uranium deposits are usually sourced from radioactive granites, where certain minerals such as monazite are leached during hydrothermal a...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Nickel
Nickel deposits are generally found in two forms, either as sulfide or laterite. Sulfide type nickel deosits are formed in essentially th...   » Read the article

Encyclopedia - Scandium: Encyclopedia Ii - Scandium - History
Dmitri Mendeleev used his periodic law, in 1869, to predict the existence and some properties of three unknown elements including one he ...   » Read the article

Encyclopedia - Scandium: Encyclopedia Ii - Scandium - Occurrence
Rare minerals from Scandinavia and Madagascar such as thortveitite, euxenite and gadolinite are the only known concentrated sources of th...   » Read the article

Encyclopedia - Scandium: Encyclopedia Ii - Scandium - Isotopes
Naturally occurring scandium is composed of 1 stable isotope Sc-45. 13 radioisotopes have been characterized with the most stable being S...   » Read the article

Encyclopedia - Zinc-carbon Battery: Encyclopedia Ii - Zinc-carbon Battery - Leakage
When the dry cell has been used for a certain time, the zinc container becomes thinner because zinc metal is oxidised to zinc ions. Moreo...   » Read the article

Encyclopedia - Tungsten: Encyclopedia Ii - Tungsten - History
Tungsten (Swedish and Danish tung sten meaning "heavy stone", even though the current name for the element in Swedish is volfram) was fir...   » Read the article

Encyclopedia - Tungsten: Encyclopedia Ii - Tungsten - Biological Role
Enzymes called oxidoreductases use tungsten in a way that is similar to molybdenum by using it in a tungsten-pterin complex. On August 20...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Rare Earth Elements Niobium Tantalum Lithium
The overwhelming majority of rare earth elements, tantalum and lithium are found within pegmatite. Ore genesis theories for these ores ar...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - Applications
Approximately 95% of titanium production is consumed in the form of titanium dioxide (TiO2), an intensely white permanent pigment with go...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Tin Tungsten And Molybdenum
These three metals generally form in a certain type of granite, via a similar mechanism to intrusive-related gold and copper. They are co...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Platinum
Platinum and palladium are precious metals generally found in ultramafic rocks. The source of platinum and palladium deposits is ultramaf...   » Read the article

Encyclopedia - Chlorite: Encyclopedia Ii - Chlorite - Definition
The chlorite ion is ClO2-. A chlorite (compound) is a compound that contains this group, with chlorine in oxidation state +3. ... See a...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Iron
Iron ores are overwhelmingly derived from ancient sediments known as banded iron formations (BIFs). These sediments are composed of iron ...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Industrial Process Design
Typically an industrial process will use an extraction step in which solutes are transferred from the aqueous phase to the organic phase,...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Classification Of Ore Deposits
Ore deposits are usually classified by ore formation processes and geological setting. For example, SEDEX deposits, literally meaning "se...   » Read the article

Encyclopedia - Chlorite: Encyclopedia Ii - Chlorite - Dicussion
Chlorites are salts of chlorous acid. How does the chlorite anion fit within the overall scheme of chlorine based anions? In general, chl...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Distribution Ratio
In solvent extraction a distribution ratio is oftein quoted as a measure of how well extracted a species is. The distribution ratio (D) i...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Multistage Countercurrent Continuous Processes
These are commonly used in industry for the processing of metals such as the lanthanides, because the separation factors between the lant...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Extraction Without Chemical Change
Some solutes such as noble gases can be extracted from one phase to another without the need for a chemical reaction (See Absorption (che...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Aqueous Complexing Agents
If a complexing agent is present in the aqueous phase then it can lower the distribution ratio. For instance in the case of iodine being ...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Lead Zinc Silver
Lead-zinc deposits are generally accompanied by silver, hosted within the lead sulfide galena or within the zinc sulfide sphalerite. Lead...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Distribution Ratio
In solvent extraction a distribution ratio is oftein quoted as a measure of how well extracted a species is. The distribution ratio (D) i...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - Isotopes
Naturally occurring titanium is composed of 5 stable isotopes; Ti-46, Ti-47, Ti-48, Ti-49 and Ti-50 with Ti-48 being the most abundant (7...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - Occurrence And Production
Titanium metal is not found unbound to other elements in nature but the element is the ninth most abundant element in the Earth's crust (...   » Read the article

Encyclopedia - Ore Genesis: Encyclopedia Ii - Ore Genesis - Gold
Gold deposits are formed via a very wide variety of geological processes. Deposits are classified as primary, alluvial or placer deposits...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Separation Factors
The separation factor is one distribution ratio divided by another, it is a measure of the ability of the system to separate two solutes....   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Extraction Without Chemical Change
Some solutes such as noble gases and osmium tetoxide can be extracted from one phase to another without the need for a chemical reaction....   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Multistage Countercurrent Continuous Processes
These are commly used in industry for the processing of metals such as the lanthanides, because the separation factors between the lantha...   » Read the article

Encyclopedia - Liquid-liquid Extraction: Encyclopedia Ii - Liquid-liquid Extraction - Batchwise Single Stage Extractions
This is commonly used on the small scale in chemical labs, it is normal to use a separating funnel For instance if a chemist was to extra...   » Read the article

Encyclopedia - Titanium: Encyclopedia Ii - Titanium - History
Titanium (Latin Titans, Earth or the first sons of Gaia) was discovered in England by Reverend William Gregor in 1791. He recognised the ...   » Read the article

Encyclopedia - Potassium Permanganate: Encyclopedia Ii - Potassium Permanganate - Cautions
Solid KMnO4 is a very strong oxidizer, which when mixed with pure glycerine, will cause a highly exothermic chemical reaction to take pla...   » Read the article

Encyclopedia - Beagle 2: Encyclopedia Ii - Beagle 2 - Spacecraft And Subsystems
Beagle 2 had a robotic arm known as the Payload Adjustable Workbench (PAW), designed to be extended after landing. The PAW contained a pa...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Alkanes In Nature
Although alkanes occur in nature in various way, they do not rank biologically among the essential materials. Cycloalkanes with 14 to 18 ...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Reactions
Alkane - Reactions with oxygen. All alkanes react with oxygen in a combustion reaction, although they become increasing difficult to ig...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Properties
Alkane - Physical properties. The molecular structure, particularly the surface area of the molecule, determines the boiling point of t...   » Read the article

Encyclopedia - Beagle 2: Encyclopedia Ii - Beagle 2 - Mission Profile
Mars Express launched from Baikonur at 17:45 UTC (18:45 BST) on 2 June 2003. The Beagle 2 was a Mars lander initially mounted on the top ...   » Read the article

Encyclopedia - Beagle 2: Encyclopedia Ii - Beagle 2 - Mission Progress
Although the Beagle 2 craft successfully deployed from the Mars Express "mother ship", confirmation of a successful landing was not forth...   » Read the article

Encyclopedia - Chlorate: Encyclopedia Ii - Chlorate - Examples
See category for a bigger list. ... See also:Chlorate, Chlorate - Definition, Chlorate - Examples, Chlorate - Preparation, Chlorate - ...   » 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 - Beagle 2: Encyclopedia Ii - Beagle 2 - Esa/uk Inquiry Report
In May, 2004, the report form the Commission of Inquiry on Beagle 2 was submitted to ESA and the UK's science minister Lord Sainsbury. In...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Occurrence
Alkanes occur both on Earth and in the solar system, however only the first hundred or so, and even then mostly only in traces. The light...   » Read the article

Encyclopedia - Alkane: Encyclopedia Ii - Alkane - Nomenclature Of Alkanes
The names of all alkanes end with -ane. Alkane - Alkanes with unbranched carbon chains. The first four members of the series (in terms ...   » 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 - 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 - 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 - 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 - Zinc: Encyclopedia Ii - Zinc - History
Zinc alloys have been used for centuries, as brass goods dating to 1000-1400 BC have been found in Palestine and zinc objects with 87% zi...   » Read the article

Encyclopedia - Zinc: Encyclopedia Ii - Zinc - Biological Role
Zinc is an essential element, necessary for sustaining all life. It is estimated that 3000 of the hundreds of thousands of proteins in th...   » Read the article

Encyclopedia - Acid Dissociation Constant: Encyclopedia Ii - Acid Dissociation Constant - Relationship Between Acidity And Basicity Constants
There exists a relationship between the value of Ka for an acid HA and the value of Kb for its conjugate base A–. Since adding the ioni...   » Read the article

Encyclopedia - Acid Dissociation Constant: Encyclopedia Ii - Acid Dissociation Constant - Basicity Constant Of The Conjugate Base
By analogy, one can define the basicity constant (Kb) and the pKb of the conjugate base A–: pKb = −log10Kb T...   » Read the article

Encyclopedia - Zinc: Encyclopedia Ii - Zinc - Zinc Production
There are zinc mines throughout the world, with the largest producers being Australia, Canada, China, Peru and the U.S.A. Mines in Europe...   » Read the article

Encyclopedia - Chlorate: Encyclopedia Ii - Chlorate - Preparation
Metal chlorates can be prepared by adding Chlorine to hot metal hydroxides, for example, KClO3: 3Cl2 + 6KOH → 5KCl + KClO3 + 3H2O ......   » Read the article

Encyclopedia - Goldiii Chloride: Encyclopedia Ii - Goldiii Chloride - Structure
AuCl3 exists as a dimer both as a solid and as a vapour; the bromide AuBr3 follows the same pattern. This is similar (but not identical)...   » Read the article

Encyclopedia - Phosphorus Trichloride: Encyclopedia Ii - Phosphorus Trichloride - Preparation
Phosphorus trichloride is prepared industrially by the reaction of chlorine with a refluxing solution of white phosphorus in phosphorus t...   » Read the article

Encyclopedia - Perchlorate: Encyclopedia Ii - Perchlorate - Scientific Definition
The perchlorate ion is ClO4-. A perchlorate (compound) is a compound containing this group, with chlorine in oxidation state +7. ... Se...   » Read the article

Encyclopedia - Oxide: Encyclopedia Ii - Oxide - Types Of Oxides
Oxides of more electropositive elements tend to be basic. They are called basic anhydrides; adding water, they may form basic hydroxides....   » Read the article

Encyclopedia - Oxide: Encyclopedia Ii - Oxide - Chemical Properties
Oxides are formed in redox reactions through oxidation in which a reducing agent is allowed to react with molecular oxygen (O2) or oxidiz...   » Read the article

Encyclopedia - Phosphorus Trichloride: Encyclopedia Ii - Phosphorus Trichloride - Uses
World production exceeds one-third of a million tonnes[1]. Phosphorus trichloride is an important starting point for the manufacture of m...   » Read the article