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Heinrich Biltz
Heinrich Biltz (26 May 1865 – 29 October 1943) was a German chemist and professor. Life and career Heinrich Biltz was the son of Karl Friedrich Biltz who was a literary scholar and theatre critic His brother Wilhelm Biltz was also a noted chemist. After his university entrance diploma at the Royal Grammar School (Königliches Wilhelm-Gymnasium) in Berlin in 1885 Heinrich began studying chemistry in the Humboldt University of Berlin with August Wilhelm von Hofmann. later studying at the University of Göttingen with Victor Meyer. In 1888 he was awarded his doctorate in natural science with the continuation of research commenced by Victor Meyer on the molecular weight of substances at high temperatures. During this time he also determined the vapour density from Tin (II) chloride and Sulphur. From 8 July 1891 to 1897, Heinrich was a professor of chemistry at the University of Greifswald. In 1897 he became a professor of the Department of Inorganic Chemistry at the Universi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berlin
Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constituent states, Berlin is surrounded by the State of Brandenburg and contiguous with Potsdam, Brandenburg's capital. Berlin's urban area, which has a population of around 4.5 million, is the second most populous urban area in Germany after the Ruhr. The Berlin-Brandenburg capital region has around 6.2 million inhabitants and is Germany's third-largest metropolitan region after the Rhine-Ruhr and Rhine-Main regions. Berlin straddles the banks of the Spree, which flows into the Havel (a tributary of the Elbe) in the western borough of Spandau. Among the city's main topographical features are the many lakes in the western and southeastern boroughs formed by the Spree, Havel and Dahme, the largest of which is Lake Müggelsee. Due to its l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilhelm Biltz
Wilhelm Biltz (8 March 1877 – 13 November 1943) was a German chemist and scientific editor. In addition to his scholarly work, Biltz is noted for commanding the principal German tank involved in the first ever tank-on-tank battle in history at the Second Battle of Villers-Bretonneux. Life and career Wilhelm Biltz was the son of Karl Friedrich Biltz who was a literary scholar and theatre critic. His older brother, Heinrich Biltz, was also a noted chemist. Education After his university entrance diploma at the Royal Grammar School (Königliches Wilhelm-Gymnasium) in Berlin in 1895 and influenced by his elder brother Heinrich, Wilhelm Biltz began studying chemistry in the Humboldt University of Berlin, the University of Heidelberg and continued his studies in 1898 with professor Friedrich Wilhelm Semmler in the University of Greifswald where he was awarded his doctorate in natural science with research on the chemistry of Terpenes. Academic career From 1900 Wilhelm Biltz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Industry
The chemical industry comprises the companies that produce industrial chemicals. Central to the modern world economy, it converts raw materials (oil, natural gas, air, water, metals, and minerals) into more than 70,000 different products. The plastics industry contains some overlap, as some chemical companies produce plastics as well as chemicals. Various professionals are involved in the chemical industry including chemical engineers, chemists and lab technicians. History Although chemicals were made and used throughout history, the birth of the heavy chemical industry (production of chemicals in large quantities for a variety of uses) coincided with the beginnings of the Industrial Revolution. Industrial Revolution One of the first chemicals to be produced in large amounts through industrial processes was sulfuric acid. In 1736 pharmacist Joshua Ward developed a process for its production that involved heating saltpeter, allowing the sulfur to oxidize and combine with water ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidising Agent
An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxidizer is any substance that oxidizes another substance. The oxidation state, which describes the degree of loss of electrons, of the oxidizer decreases while that of the reductant increases; this is expressed by saying that oxidizers "undergo reduction" and "are reduced" while reducers "undergo oxidation" and "are oxidized". Common oxidizing agents are oxygen, hydrogen peroxide and the halogens. In one sense, an oxidizing agent is a chemical species that undergoes a chemical reaction in which it gains one or more electrons. In that sense, it is one component in an oxidation–reduction (redox) reaction. In the second sense, an oxidizing agent is a chemical species that transfers electronegative atoms, usually oxygen, to a substrate. Combus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bonds ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albert Ladenburg
Albert Ladenburg (July 2, 1842August 15, 1911) was a German chemist. Early life and education Ladenburg was a member of the well-known Jewish in Mannheim. He was educated at a Realgymnasium at Mannheim and then, after the age of 15, at the technical school of Karlsruhe, where he studied mathematics and modern languages. He then proceeded to the University of Heidelberg where he studied chemistry and physics with Robert Bunsen. He also studied physics in Berlin. He got his Ph.D. in Heidelberg. Academic career In 1873, Ladenburg went to Kiel as professor of chemistry and director of the laboratory, remaining there until 1889 when he went to the University of Breslau in the same capacity. He was made an honorary member of the Pharmaceutical Society of Great Britain in 1886 and received the Hanbury Medal for original research in chemistry in 1889. Ladenburg isolated hyoscine, also known as scopolamine for the first time in 1880. In 1900 Ladenburg founded the ''Chemische Gesells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seizure
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with loss of consciousness ( tonic-clonic seizure), to shaking movements involving only part of the body with variable levels of consciousness (focal seizure), to a subtle momentary loss of awareness ( absence seizure). Most of the time these episodes last less than two minutes and it takes some time to return to normal. Loss of bladder control may occur. Seizures may be provoked and unprovoked. Provoked seizures are due to a temporary event such as low blood sugar, alcohol withdrawal, abusing alcohol together with prescription medication, low blood sodium, fever, brain infection, or concussion. Unprovoked seizures occur without a known or fixable cause such that ongoing seizures are likely. Unprovoked seizures may be exacerbated by stress or sl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenytoin
Phenytoin (PHT), sold under the brand name Dilantin among others, is an anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The intravenous form, fosphenytoin, is used for status epilepticus that does not improve with benzodiazepines. It may also be used for certain heart arrhythmias or neuropathic pain. It can be taken intravenously or by mouth. The intravenous form generally begins working within 30 minutes and is effective for roughly 24 hours. Blood levels can be measured to determine the proper dose. Common side effects include nausea, stomach pain, loss of appetite, poor coordination, increased hair growth, and enlargement of the gums. Potentially serious side effects include sleepiness, self harm, liver problems, bone marrow suppression, low blood pressure, and toxic epidermal necrolysis. There is evidence that use during pregnancy results in abnormalities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inorganic Chemistry
Inorganic chemistry deals with synthesis and behavior of inorganic and organometallic compounds. This field covers chemical compounds that are not carbon-based, which are the subjects of organic chemistry. The distinction between the two disciplines is far from absolute, as there is much overlap in the subdiscipline of organometallic chemistry. It has applications in every aspect of the chemical industry, including catalysis, materials science, pigments, surfactants, coatings, medications, fuels, and agriculture. Key concepts Many inorganic compounds are ionic compounds, consisting of cations and anions joined by ionic bonding. Examples of salts (which are ionic compounds) are magnesium chloride MgCl2, which consists of magnesium cations Mg2+ and chloride anions Cl−; or sodium oxide Na2O, which consists of sodium cations Na+ and oxide anions O2−. In any salt, the proportions of the ions are such that the electric charges cancel out, so that the bulk compound is e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulphur
Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Today, almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum.. Downloahere The greatest commercial use of the element is the production o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tin (II) Chloride
Tin(II) chloride, also known as stannous chloride, is a white crystalline solid with the formula . It forms a stable dihydrate, but aqueous solutions tend to undergo hydrolysis, particularly if hot. SnCl2 is widely used as a reducing agent (in acid solution), and in electrolytic baths for tin-plating. Tin(II) chloride should not be confused with the other chloride of tin; tin(IV) chloride or stannic chloride (SnCl4). Chemical structure SnCl2 has a lone pair of electrons, such that the molecule in the gas phase is bent. In the solid state, crystalline SnCl2 forms chains linked via chloride bridges as shown. The dihydrate is also three-coordinate, with one water coordinated on to the tin, and a second water coordinated to the first. The main part of the molecule stacks into double layers in the crystal lattice, with the "second" water sandwiched between the layers. Chemical properties Tin(II) chloride can dissolve in less than its own mass of water without apparent decomposition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapour Density
Vapour density is the density of a vapour in relation to that of hydrogen. It may be defined as mass of a certain volume of a substance divided by mass of same volume of hydrogen. :vapour density = mass of ''n'' molecules of gas / mass of ''n'' molecules of hydrogen. :vapour density = molar mass of gas / molar mass of H2 :vapour density = molar mass of gas / 2.016 :vapour density = × molar mass (and thus: molar mass = ~2 × vapour density) For example, vapour density of mixture of NO2 and N2O4 is 38.3. Vapour density is a dimensionless quantity. Alternative definition In many web sources, particularly in relation to safety considerations at commercial and industrial facilities in the U.S., vapour density is defined with respect to air, not hydrogen. Air is given a vapour density of one. For this use, air has a molecular weight of 28.97 atomic mass units, and all other gas and vapour molecular weights are divided by this number to derive their vapour density. For example, acet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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