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Roentgenium
Roentgenium () is a synthetic chemical element; it has symbol Rg and atomic number 111. It is extremely radioactive and can only be created in a laboratory. The most stable known isotope, roentgenium-282, has a half-life of 130 seconds, although the unconfirmed roentgenium-286 may have a longer half-life of about 10.7 minutes. Roentgenium was first created in December 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the physicist Wilhelm Röntgen ( also spelled Roentgen), who discovered X-rays. Only a few roentgenium atoms have ever been synthesized, and they have no practical application. In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 11 elements, although no chemical experiments have been carried out to confirm that it behaves as the heavier homologue to gold in group 11 as the ninth member of the 6d series of transition metals. Roentgenium is cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discovery Of The Chemical Elements
The discoveries of the 118 chemical elements known to exist as of 2025 are presented here in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesize more elements, and it is not known how many elements are possible. Each element's list of elements by name, name, atomic number, year of first report, name of the discoverer, and notes related to the discovery are listed. Periodic table of elements Graphical timeline ImageSize = width:1600 height:120 # barincrement:0 PlotArea = top:70 bottom:30 right:10 left:10 AlignBars = justify Colors = id:gray1 value:gray(0.85) legend:Independent id:gray2 value:gray(0.95) DateFormat = yyyy Period = from:1665 till:2025 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:10 start:1670 ScaleMinor = unit:year increment:1 start:1665 TextData = tex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group 11 Element
Group 11, by modern IUPAC numbering, is a group (periodic table), group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that roentgenium behaves like the heavier Homologous series, homologue to gold. Group 11, more specifically, the first three members are also known as the ''coinage metals'', due to their usage in minting coins—while the rise in metal prices mean that silver and gold are no longer used for circulating currency, remaining in use for bullion, copper remains a common metal in coins to date, either in the form of copper Cladding (metalworking), clad coinage or as part of the cupronickel alloy. They were most likely the first three elements discovered. Copper, silver, and gold all occur naturally in native element, elemental form. History All three stable elements of the group have been known since prehistoric times, as all of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Element
A synthetic element is a known chemical element that does not occur naturally on Earth: it has been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, it is called "synthetic", "artificial", or "man-made". The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: these 24 elements were first created between 1944 and 2010. The mechanism for the creation of a synthetic element is to force additional protons into the Atomic nucleus, nucleus of an element with an atomic number lower than 95. All known (see: Island of stability) synthetic elements are unstable, but they radioactive decay, decay at widely varying rates; the half-lives of their longest-lived isotopes range from microseconds to millions of years. Five more elements that were first created artificially are strictly speaking not ''synthetic'' because they were later found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sigurd Hofmann
Sigurd Hofmann (15 February 1944 – 17 June 2022) was a German physicist known for his work on superheavy elements. Biography Hofmann was born in Böhmisch Kamnitz, Nazi Germany (now Česká Kamenice, Czech Republic) on 15 February 1944. He discovered his love for physics at the Max Planck High School in Groß-Umstadt, Germany, where he graduated in 1963. He studied physics at the Technical University in Darmstadt (Diploma, 1969, and thesis at the Institute of Nuclear Physics with Egbert Kankeleit and Karl Wien, 1974). From 1974 to 1989 he was responsible for the detection and identification of nuclei produced in heavy ion reactions at the velocity separator SHIP (Separator for Heavy Ion reaction Products) at the GSI Helmholtz Centre for Heavy Ion Research. He was working in the Department Nuclear Chemistry II headed by Peter Armbruster. From 1989 he was leading, after Gottfried Münzenberg, the experiments for the synthesis of new elements. From 1998 he was Honorary Pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Symbol
Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised. History Earlier symbols for chemical elements stem from classical Latin and Greek language, Greek words. For some elements, this is because the material was known in ancient times, while for others, the name is a more recent invention. For example, Pb is the symbol for lead (''plumbum'' in Latin); Hg is the symbol for mercury (element), mercury (''hydrargyrum'' in Greek); and He is the symbol for helium (a Neo-Latin name) because helium was not known in ancient Roman times. Some symbols come from other sources, like W for tungsten (''Wolfram'' in German) which was not known in Roman times. A three-letter Systematic element name, temporary sym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transition Metal
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded. The lanthanide and actinide elements (the f-block) are called inner transition metals and are sometimes considered to be transition metals as well. They are lustrous metals with good electrical and thermal conductivity. Most (with the exception of group 11 and group 12) are hard and strong, and have high melting and boiling temperatures. They form compounds in any of two or more different oxidation states and bind to a variety of ligands to form coordination complexes that are often coloured. They form many useful alloys and are often employed as catalysts in elemental form or in compounds such as coordination complexes and oxides. Most are strongly paramagnetic because of their unpaired d electrons, as are many of their compounds. All of the elements that are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Period 7 Element
A period 7 element is one of the chemical elements in the seventh row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases: a new row is begun when chemical behavior begins to repeat, meaning that elements with similar behavior fall into the same vertical columns. The seventh period contains 32 elements, tied for the most with period 6, beginning with francium and ending with oganesson, the heaviest element currently discovered. As a rule, period 7 elements fill their 7s shells first, then their 5f, 6d, and 7p shells in that order, but there are exceptions, such as uranium. Properties All period 7 elements are radioactive. This period contains the actinides, which include plutonium, the last naturally occurring element; subsequent elements must be created artificially. While the first five of these synthetic elemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transactinide Element
Superheavy elements, also known as transactinide elements, transactinides, or super-heavy elements, or superheavies for short, are the chemical elements with atomic number greater than 104. The superheavy elements are those beyond the actinides in the periodic table; the last actinide is lawrencium (atomic number 103). By definition, superheavy elements are also transuranium elements, i.e., having atomic numbers greater than that of uranium (92). Depending on the definition of group 3 adopted by authors, lawrencium may also be included to complete the 6d series. Glenn T. Seaborg first proposed the actinide concept, which led to the acceptance of the actinide series. He also proposed a transactinide series ranging from element 104 to 121 and a superactinide series approximately spanning elements 122 to 153 (though more recent work suggests the end of the superactinide series to occur at element 157 instead). The transactinide seaborgium was named in his honor. Superheavies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roentgen2
Röntgen or Roentgen may refer to: * Roentgen (unit), unit of measurement for ionizing radiation, named after Wilhelm Röntgen * Wilhelm Röntgen (1845–1923), German physicist, discoverer of X-rays * Abraham Roentgen (1711–1793), German cabinetmaker * David Roentgen (1743–1807), German cabinetmaker, son of Abraham Roentgen * Gerhard Moritz Roentgen (1795–1852), Dutch and German entrepreneur and engineer * Engelbert Röntgen (1829–1897), German-Dutch violinist * Heinrich Röntgen (1787–1813), German explorer * Julius Röntgen (1855–1932), German-Dutch composer of classical music, son of Engelbert Röntgen * Kevin Roentgen Kevin Roentgen (pronounced "rent-gehn") is an American singer, songwriter, record producer and formerly guitarist for the rock band Orson, who is currently based in Nashville, Tennessee. Roentgen is previously known for fronting L.A. rock band ..., musician, singer with American rock band Orson * ''Roentgen'' (album), by Japanese singer Hyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel
Nickel is a chemical element; it has symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive, but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope
Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemical element), but different nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties. The term isotope is derived from the Greek roots isos (wikt:ἴσος, ἴσος "equal") and topos (wikt:τόπος, τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd (doctor), Margaret Todd in a 1913 suggestion to the British chemist Frederick Soddy, who popularized the term. The number of protons within the atomic nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JINR
The Joint Institute for Nuclear Research (JINR, ), in Dubna, Moscow Oblast (110 km north of Moscow), Russia, is an international research center for nuclear sciences, with 5,500 staff members including 1,200 researchers holding over 1,000 Ph.D.s from eighteen countries. Most scientists are scientists of the Russian Federation. The institute has seven laboratories, each with its own specialisation: theoretical physics, high energy physics (particle physics), heavy ion physics, condensed matter physics, nuclear reactions, neutron physics, and information technology. The institute has a division to study radiation and radiobiological research and other ad hoc experimental physics experiments. Principal research instruments include a nuclotron superconductive particle accelerator (particle energy: 7 GeV), three isochronous cyclotrons (120, 145, 650 MeV), a phasitron (680 MeV) and a synchrophasotron (4 GeV). The site has a neutron fast-pulse reactor (1,500MW pulse) with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
