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Misidentified Chemical Elements
Chemical element A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its ...s that have been mistakenly "discovered". Further investigation showed that their discovery was either mistaken, that they have been mistaken from an already-known element, or mixture of two elements, or that they indicated a failing in theory where a new element had been assumed rather than some previously unknown behaviour. References {{DEFAULTSORT:Misidentified chemical elements Chemistry-related lists ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Element
A chemical element is a chemical substance whose atoms all have the same number of protons. The number of protons is called the atomic number of that element. For example, oxygen has an atomic number of 8: each oxygen atom has 8 protons in its atomic nucleus, nucleus. Atoms of the same element can have different numbers of neutrons in their nuclei, known as isotopes of the element. Two or more atoms can combine to form molecules. Some elements form Homonuclear molecule, molecules of atoms of said element only: e.g. atoms of hydrogen (H) form Diatomic molecule, diatomic molecules (H). Chemical compounds are substances made of atoms of different elements; they can have molecular or non-molecular structure. Mixtures are materials containing different chemical substances; that means (in case of molecular substances) that they contain different types of molecules. Atoms of one element can be transformed into atoms of a different element in nuclear reactions, which change an atom's at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Huggins
Sir William Huggins (7 February 1824 – 12 May 1910) was a British astronomer best known for his pioneering work in astronomical spectroscopy together with his wife, Margaret. Biography William Huggins was born at Cornhill, Middlesex, in 1824. In 1875, he married Margaret Lindsay, daughter of John Murray of Dublin, who also had an interest in astronomy and scientific research. She encouraged her husband's photography and helped to put their research on a systematic footing. Huggins built a private observatory at 90 Upper Tulse Hill, London, from where he and his wife carried out extensive observations of the spectral emission lines and absorption lines of various celestial objects. On 29 August 1864, Huggins was the first to take the spectrum of a planetary nebula when he analysed NGC 6543. He was also the first to distinguish between nebulae and galaxies by showing that some (like the Orion Nebula) had pure emission spectra characteristic of gas, while others like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thorium
Thorium is a chemical element; it has symbol Th and atomic number 90. Thorium is a weakly radioactive light silver metal which tarnishes olive grey when it is exposed to air, forming thorium dioxide; it is moderately soft, malleable, and has a high melting point. Thorium is an electropositive actinide whose chemistry is dominated by the +4 oxidation state; it is quite reactive and can ignite in air when finely divided. All known thorium isotopes are unstable. The most stable isotope, 232Th, has a half-life of 14.05 billion years, or about the age of the universe; it decays very slowly via alpha decay, starting a decay chain named the thorium series that ends at stable 208 Pb. On Earth, thorium and uranium are the only elements with no stable or nearly-stable isotopes that still occur naturally in large quantities as primordial elements. Thorium is estimated to be over three times as abundant as uranium in the Earth's crust, and is chiefly refined from monazite sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium
Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875, elemental gallium is a soft, silvery metal at standard temperature and pressure. In its liquid state, it becomes silvery white. If enough force is applied, solid gallium may fracture conchoidal fracture, conchoidally. Since its discovery in 1875, gallium has widely been used to make alloys with low melting points. It is also used in semiconductors, as a dopant in semiconductor substrates. The melting point of gallium, , is used as a temperature reference point. Gallium alloys are used in thermometers as a non-toxic and environmentally friendly alternative to Mercury (element), mercury, and can withstand higher temperatures than mercury. A melting point of , well below the freezing point of water, is claimed for the alloy galinstan (62–95% gallium, 5–22% indium, and 0–16% tin by weight), but that may be t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monatshefte Für Chemie
''Monatshefte für Chemie - Chemical Monthly'' is a journal covering recent research from all branches of chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules a .... It was originally conceived as an Austrian journal, but has evolved into an international journal covering all branches of chemistry. References {{chem-journal-stub Academic journals established in 1880 Chemistry journals English-language journals Monthly journals Springer Science+Business Media academic journals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthite
Allanite (also called orthite) is a sorosilicate group of minerals within the broader epidote group that contain a significant amount of rare-earth elements. The mineral occurs mainly in metamorphosed clay-rich sediments and felsic igneous rocks. It has the general formula A2M3Si3O12 H where the A sites can contain large cations such as Ca2+, Sr2+, and rare-earth elements, and the M sites admit Al3+, Fe3+, Mn3+, Fe2+, or Mg2+ among others. However, a large amount of additional elements, including Th, U, Be, Zr, P, Ba, Cr and others may be present in the mineral. The International Mineralogical Association lists four minerals in the allanite group, each recognized as a unique mineral: allanite-(Ce), allanite-(La), allanite-(Nd), and allanite-(Y), depending on the dominant rare earth present: cerium, lanthanum, neodymium or yttrium. Allanite contains up to 20% rare-earth elements and is a valuable source of them. The inclusion of thorium and other radioactive elements in allanite re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rare-earth Mineral
A rare-earth mineral contains one or more rare-earth elements as major metal constituents. Rare-earth minerals are usually found in association with alkaline to peralkaline igneous magmas in pegmatites or with carbonatite Intrusive rock, intrusives. Perovskite (structure), Perovskite mineral phases are common hosts to rare-earth elements within the alkaline complexes. Minerals are solids composed of various inorganic elements, mixed through processes such as evaporation, pressure or other physical changes. Rare earth minerals are rare because rare earth elements have unique geochemical properties that prevent them from easily forming minerals, and are therefore not normally found in deposits large or concentrated enough for mining. This is the reason they are called "rare" earths. These elements have a wide range of uses from every day items to military technologies. The minerals that do exist are often associated with alkaline magmas or with carbonatite Intrusive rock, intrusive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Line
A spectral line is a weaker or stronger region in an otherwise uniform and continuous spectrum. It may result from emission (electromagnetic radiation), emission or absorption (electromagnetic radiation), absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules. These "fingerprints" can be compared to the previously collected ones of atoms and molecules, and are thus used to identify the atomic and molecular components of stars and planets, which would otherwise be impossible. Types of line spectra Spectral lines are the result of interaction between a Quantum mechanics, quantum system (usually atoms, but sometimes molecules or atomic nucleus, atomic nuclei) and a single photon. When a photon has about the right amount of photon energy, energy (which is connected to its frequency) to allow a change in the energy state of the system (in the case of an atom this is usually an electron cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eduard Linnemann
Eduard Linnemann (2 February 1841 – 4 April 1886) was a German chemist. He studied chemistry at the University of Heidelberg and at the University of Karlsruhe. After he received his Ph.D. he worked with Kekulé at the University of Ghent and with Leopold von Pebal at the University of Lemberg. He was appointed professor at the University of Lemberg in 1865, changed to Deutsche Technische Hochschule Brünn from 1872 until 1875 and then became professor at the Charles University in Prague. He held this position until his death in 1886. He is known for his investigations of mannitol and his analyses of zircon. In 1886, he proposed the name " austrium" for what he believed was a new chemical element. Publications * ''Über das Unvermögen des Propylens sich mit Wasser zu verbinden'', 1877 - On the inability of propylene to combine with water. * ''Über die Absorptionserscheinungen in Zirkonen'', 1885 - On the absorption phenomena of zircon. * ''Das Oxydationsproduct des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium
Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875, elemental gallium is a soft, silvery metal at standard temperature and pressure. In its liquid state, it becomes silvery white. If enough force is applied, solid gallium may fracture conchoidal fracture, conchoidally. Since its discovery in 1875, gallium has widely been used to make alloys with low melting points. It is also used in semiconductors, as a dopant in semiconductor substrates. The melting point of gallium, , is used as a temperature reference point. Gallium alloys are used in thermometers as a non-toxic and environmentally friendly alternative to Mercury (element), mercury, and can withstand higher temperatures than mercury. A melting point of , well below the freezing point of water, is claimed for the alloy galinstan (62–95% gallium, 5–22% indium, and 0–16% tin by weight), but that may be t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austrium
Austrium is the name of a new chemical element proposed by Eduard Linnemann in 1886. As a chemist at the German University in Prague he experimented with the mineral orthite (from Arendal in Norway). In the course of his works over several years he detected spectral lines at 4165 and 4030 Angstrom, respectively, which he was not able to ascribe to any then known element. These findings were published only after his death after due consideration on May 6, 1886, by the Academy of Sciences of Prague. Subsequently, the French chemist Paul Emile Lecoq de Boisbaudran pointed out that Linnemann's findings could also be attributed to gallium Gallium is a chemical element; it has Chemical symbol, symbol Ga and atomic number 31. Discovered by the French chemist Paul-Émile Lecoq de Boisbaudran in 1875, elemental gallium is a soft, silvery metal at standard temperature and pressure. ..., an element which had been described by Lecoq himself in 1875. Finally, Richard Pribram from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
