341 relations: Abundance of elements in Earth's crust, Acerinox accident, Acetate, Acid–base reaction, Acrylic acid, Albert Einstein, Alkali metal, Alkalide, Alkaline earth metal, Alkene, Alloy, Alum, Aluminium, Aluminium oxide, Aluminium sulfate, Amalgam (chemistry), American Chemical Society, Ammonia, Ammonium carbonate, Ampoule, Angewandte Chemie, Anhydrous, Annalen der Physik, Anthraquinone, Antimony, Argon, Arsenic poisoning, Atmosphere of Earth, Atomic clock, Atomic mass, Atomic number, August Kekulé, Aulus Gellius, Autoignition temperature, Avogadrite, Azide, Bad Dürkheim, Barium, Base (chemistry), Becquerel, Bernic Lake, Beryl, Beta decay, Bikita District, Biosphere, Bismuth, Boiling point, Borate minerals, Borosilicate glass, Cabot Corporation, ..., Cadmium, Cadmium chloride, Caesium auride, Caesium bromide, Caesium chloride, Caesium fluoride, Caesium hydroxide, Caesium iodide, Caesium nitrate, Caesium oxide, Caesium standard, Caesium-137, Calcium carbonate, Calcium chloride, CANDU Owners Group, Carbon, Carbon dioxide, Carbonate, Cardiac arrest, Carnallite, Cathode, Chalcogen, Chemical element, Chernobyl disaster, Chloroplatinic acid, Chromate and dichromate, Cobalt, Colloid, Completion (oil and gas wells), Coordination number, Copernicium, Copper, Cubic crystal system, Curie, Cyanide, Cyclic compound, Dangerous goods, Deep Space 1, Differential centrifugation, Dirty bomb, Dosimetry, Double salt, Drilling fluid, Ductility, Electrical resistivity and conductivity, Electrolysis, Electromagnetic radiation, Electron, Electron density, Electronegativity, Emission spectrum, Energy level, Epilepsy, Erongo Region, Ester, Etching, Ethanol, Ethylene oxide, Exhaust gas, Explosive material, Feshbach resonance, Field-emission electric propulsion, Fission product yield, Flare, Flerovium, Fluorescent lamp, Fluoride, Formate, Formic acid, Fractional crystallization (chemistry), Fractional crystallization (geology), Francium, Frequency, Gallium, Gamma ray, General Conference on Weights and Measures, Germanium, Getter, Goiânia accident, Gold, Ground state, Gustav Kirchhoff, Half-life, Halide, Halogen, Heart arrhythmia, Hertz, Hexagonal crystal family, HSAB theory, Hydrobromic acid, Hydrochloric acid, Hydrofluoric acid, Hydrogen, Hydrology, Hygroscopy, Hyperfine structure, Hypokalemia, Incompatible element, Indium, Inert gas, Infrared, Infrared spectroscopy, Intermetallic, Internal standard, International Atomic Energy Agency, International Committee for Weights and Measures, International System of Units, International Union of Pure and Applied Chemistry, Ion, Ion thruster, Ionic bonding, Ionic radius, Ionization energy, Iron, Isotope, Isotopes of barium, Isotopes of caesium, Isotopes of iodine, Isotopes of xenon, Journal of Chemical Education, Kramatorsk radiological accident, Laser, Laser cooling, Latin, Leaching (metallurgy), Lead, Lepidolite, Lewis acids and bases, List of chemical elements, Lithium, Lockheed SR-71 Blackbird, Long-lived fission product, Louis Essen, Lustre (mineralogy), Magnesium, Magnetohydrodynamic generator, Magnetometer, Manitoba, Mass number, Median lethal dose, Melting point, Mercury (element), Metal, Metallurgy, Methanol, Methyl methacrylate, Metre, Microwave, Mineral oil, Mineral water, Molar concentration, Molybdenum, N-Butyllithium, Namibia, Nanosecond, National Physical Laboratory (United Kingdom), Nature (journal), Neutron, Neutron capture, Neutron poison, Nickel, Night vision, Nigidius Figulus, Nitrate, Non-stoichiometric compound, Nuclear fallout, Nuclear fission, Nuclear fission product, Nuclear fuel cycle, Nuclear isomer, Nuclear magnetic resonance, Nuclear reactor, Nuclear weapons testing, Nucleic acid, Nucleon, Oil well, Optical character recognition, Optical fiber, Organelle, Organic chemistry, Organic synthesis, Organofluorine chemistry, Ounce, Oxalate, Oxford English Dictionary, Oxide, Oxidizing agent, Oxygen, Ozonide, Parts-per notation, Pascal (unit), Pegmatite, Periodic table, Periodic trends, Periodic Videos, Peroxide, Petalite, Pezzottaite, Phosphate, Photoelectric effect, Photomultiplier, Photosensitivity, Phthalic anhydride, Physical Review Letters, Picometre, Plasma oscillation, Platinum, Pollucite, Polymerization, Potassium, Potassium chloride, Primitive cell, Proposed redefinition of SI base units, Pseudohalogen, Pyrophoricity, Pyrotechnic colorant, Quantum mechanics, Quantum technology, R-process, Radar cross-section, Radiation therapy, Radioactive decay, Radionuclide, Rankine cycle, Rectifier, Relative atomic mass, Relativistic quantum chemistry, Robert Bunsen, Room temperature, Rubidium, Rubidium chloride, S-process, Scintillation counter, Scintillator, Second, Secondary ion mass spectrometry, Selenium, Semiconductor, Silicate, Silicon, Silver, Sodium, Sodium amide, Sodium chloride, Solar cell, Solubility, Spacecraft propulsion, Spectral line, Spectrophotometry, Spectroscopy, Spent nuclear fuel, Spin (physics), Sporocarp (fungi), Stable nuclide, Sterilization (microbiology), Stoichiometry, Strontium-90, Styrene, Suboxide, Sulfate, Sulfur, Sulfur dioxide, Sulfur trioxide, Sulfuric acid, Supernova, Superoxide, Sylvite, Tanco Mine, Tantalum, Tellurium, Thermionic converter, Thorium, Tin, Tonne, Toxicity, Toxicology and Applied Pharmacology, Trifluoroacetic acid, Tritium, Tungsten, Ultracold atom, Uranium, Vacuum tube, Video camera tube, Virus, Well logging, X-ray, Xenon, Xenon-135, Zimbabwe, Zinc bromide, Zirconium. 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The abundance of elements in Earth's crust is shown in tabulated form with the estimated crustal abundance for each chemical element shown as either percentage or parts per million (ppm) by mass (10,000 ppm.
The Acerinox accident was an incident of radioactive contamination in Cádiz (Spain).
An acetate is a salt formed by the combination of acetic acid with an alkaline, earthy, metallic or nonmetallic and other base.
An acid–base reaction is a chemical reaction that occurs between an acid and a base, which can be used to determine pH.
Acrylic acid (IUPAC: propenoic acid) is an organic compound with the formula CH2.
Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics (alongside quantum mechanics).
The alkali metals are a group (column) in the periodic table consisting of the chemical elements lithium (Li), sodium (Na), potassium (K),The symbols Na and K for sodium and potassium are derived from their Latin names, natrium and kalium; these are still the names for the elements in some languages, such as German and Russian.
An alkalide is a chemical compound in which alkali metals are anions (that is, they bear a negative charge).
The alkaline earth metals are six chemical elements in group 2 of the periodic table.
In organic chemistry, an alkene is an unsaturated hydrocarbon that contains at least one carbon–carbon double bond.
An alloy is a combination of metals or of a metal and another element.
An alum is a type of chemical compound, usually a hydrated double sulfate salt of aluminium with the general formula, where X is a monovalent cation such as potassium or ammonium.
Aluminium or aluminum is a chemical element with symbol Al and atomic number 13.
Aluminium oxide (British English) or aluminum oxide (American English) is a chemical compound of aluminium and oxygen with the chemical formula 23.
Aluminium sulfate is a chemical compound with the formula Al2(SO4)3.
An amalgam is an alloy of mercury with another metal, which may be a liquid, a soft paste or a solid, depending upon the proportion of mercury.
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry.
Ammonia is a compound of nitrogen and hydrogen with the formula NH3.
Ammonium carbonate is a salt with the chemical formula (NH4)2CO3.
An ampoule (also ampul, ampule, or ampulla) is a small sealed vial which is used to contain and preserve a sample, usually a solid or liquid.
Angewandte Chemie (meaning "Applied Chemistry") is a weekly peer-reviewed scientific journal that is published by Wiley-VCH on behalf of the German Chemical Society (Gesellschaft Deutscher Chemiker).
A substance is anhydrous if it contains no water.
Annalen der Physik (English: Annals of Physics) is one of the oldest scientific journals on physics and has been published since 1799.
Anthraquinone, also called anthracenedione or dioxoanthracene, is an aromatic organic compound with formula.
Antimony is a chemical element with symbol Sb (from stibium) and atomic number 51.
Argon is a chemical element with symbol Ar and atomic number 18.
Arsenic poisoning is a medical condition that occurs due to elevated levels of arsenic in the body.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
An atomic clock is a clock device that uses an electron transition frequency in the microwave, optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element.
The atomic mass (ma) is the mass of an atom.
The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.
Friedrich August Kekulé, later Friedrich August Kekule von Stradonitz (7 September 1829 – 13 July 1896), was a German organic chemist.
Aulus Gellius (c. 125after 180 AD) was a Latin author and grammarian, who was probably born and certainly brought up in Rome.
The autoignition temperature or kindling point of a substance is the lowest temperature at which it spontaneously ignites in normal atmosphere without an external source of ignition, such as a flame or spark.
Avogadrite ((K,Cs)BF4) is a potassium-caesium tetrafluoroborate in the halide class.
Azide is the anion with the formula N. It is the conjugate base of hydrazoic acid (HN3).
Bad Dürkheim is a spa town in the Rhine-Neckar urban agglomeration, and is the seat of the Bad Dürkheim district in Rhineland-Palatinate, Germany.
Barium is a chemical element with symbol Ba and atomic number 56.
In chemistry, bases are substances that, in aqueous solution, release hydroxide (OH−) ions, are slippery to the touch, can taste bitter if an alkali, change the color of indicators (e.g., turn red litmus paper blue), react with acids to form salts, promote certain chemical reactions (base catalysis), accept protons from any proton donor, and/or contain completely or partially displaceable OH− ions.
The becquerel (symbol: Bq) is the SI derived unit of radioactivity.
Bernic Lake is a lake in the eastern part of the province of Manitoba, Canada.
Beryl is a mineral composed of beryllium aluminium cyclosilicate with the chemical formula Be3Al2(SiO3)6.
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta ray (fast energetic electron or positron) and a neutrino are emitted from an atomic nucleus.
Bikita is a district in the Masvingo Province of Zimbabwe.
The biosphere (from Greek βίος bíos "life" and σφαῖρα sphaira "sphere") also known as the ecosphere (from Greek οἶκος oîkos "environment" and σφαῖρα), is the worldwide sum of all ecosystems.
Bismuth is a chemical element with symbol Bi and atomic number 83.
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
The borate minerals are minerals which contain a borate anion group.
Borosilicate glass is a type of glass with silica and boron trioxide as the main glass-forming constituents.
Cabot Corporation is an American specialty chemicals and performance materials company headquartered in Boston, Massachusetts.
Cadmium is a chemical element with symbol Cd and atomic number 48.
Cadmium chloride is a white crystalline compound of cadmium and chlorine, with the formula CdCl2.
Caesium auride or cesium auride (CsAu) is an ionic compound containing the unusual Au− ion, first discovered in 1978 in the laboratory of Joseph Lagowski.
Caesium bromide or cesium bromide is an ionic compound of caesium and bromine with the chemical formula CsBr.
Caesium chloride or cesium chloride is the inorganic compound with the formula CsCl.
Caesium fluoride or cesium fluoride is an inorganic compound usually encountered as a hygroscopic white solid.
Caesium hydroxide or cesium hydroxide (CsOH) is a chemical compound consisting of caesium ions and hydroxide ions.
Caesium iodide or cesium iodide (chemical formula CsI) is the ionic compound of caesium and iodine.
Caesium nitrate or cesium nitrate is a chemical compound with the chemical formula CsNO3.
Caesium oxide (IUPAC name) or cesium oxide describes inorganic compounds composed of caesium and oxygen.
The caesium standard is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency.
Caesium-137 (Cs-137), cesium-137, or radiocaesium, is a radioactive isotope of caesium which is formed as one of the more common fission products by the nuclear fission of uranium-235 and other fissionable isotopes in nuclear reactors and nuclear weapons.
Calcium carbonate is a chemical compound with the formula CaCO3.
Calcium chloride is an inorganic compound, a salt with the chemical formula CaCl2.
CANDU Owners Group is a private, not-for-profit corporation funded voluntarily by CANDU operating utilities worldwide, Canadian Nuclear Laboratories (CNL) and supplier participants.
Carbon (from carbo "coal") is a chemical element with symbol C and atomic number 6.
Carbon dioxide (chemical formula) is a colorless gas with a density about 60% higher than that of dry air.
In chemistry, a carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula of.
Cardiac arrest is a sudden loss of blood flow resulting from the failure of the heart to effectively pump.
Carnallite (also carnalite) is an evaporite mineral, a hydrated potassium magnesium chloride with formula KMgCl3·6(H2O).
A cathode is the electrode from which a conventional current leaves a polarized electrical device.
The chalcogens are the chemical elements in group 16 of the periodic table.
A chemical element is a species of atoms having the same number of protons in their atomic nuclei (that is, the same atomic number, or Z).
The Chernobyl disaster, also referred to as the Chernobyl accident, was a catastrophic nuclear accident.
Chloroplatinic acid or hexachloroplatinic acid is an inorganic compound with the formula 2(H2O)x.
Chromate salts contain the chromate anion,.
Cobalt is a chemical element with symbol Co and atomic number 27.
In chemistry, a colloid is a mixture in which one substance of microscopically dispersed insoluble particles is suspended throughout another substance.
Completion, in petroleum production, is the process of making a well ready for production (or injection).
In chemistry, crystallography, and materials science the coordination number, also called ligancy, of a central atom in a molecule or crystal is the number of atoms, molecules or ions bonded to it.
Copernicium is a synthetic chemical element with symbol Cn and atomic number 112.
Copper is a chemical element with symbol Cu (from cuprum) and atomic number 29.
In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube.
The curie (symbol Ci) is a non-SI unit of radioactivity originally defined in 1910.
A cyanide is a chemical compound that contains the group C≡N.
A cyclic compound (ring compound) is a term for a compound in the field of chemistry in which one or more series of atoms in the compound is connected to form a ring.
Dangerous goods or hazardous goods are solids, liquids, or gases that can harm people, other living organisms, property, or the environment.
Deep Space 1 (DS1) was a NASA technology demonstration spacecraft which flew by an asteroid and a comet.
Differential centrifugation is a common procedure in microbiology and cytology used to separate certain organelles from whole cells for further analysis of specific parts of cells.
A dirty bomb or radiological dispersal device (RDD) is a speculative radiological weapon that combines radioactive material with conventional explosives.
Radiation dosimetry in the fields of health physics and radiation protection is the measurement, calculation and assessment of the ionizing radiation dose absorbed by the human body.
Double salts are salts containing more than one cation or anion, and are obtained by combination of two different salts which were crystallized in the same regular ionic lattice.
In geotechnical engineering, drilling fluid is used to aid the drilling of boreholes into the earth.
Ductility is a measure of a material's ability to undergo significant plastic deformation before rupture, which may be expressed as percent elongation or percent area reduction from a tensile test.
Electrical resistivity (also known as resistivity, specific electrical resistance, or volume resistivity) is a fundamental property that quantifies how strongly a given material opposes the flow of electric current.
In chemistry and manufacturing, electrolysis is a technique that uses a direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
The electron is a subatomic particle, symbol or, whose electric charge is negative one elementary charge.
Electron density is the measure of the probability of an electron being present at a specific location.
Electronegativity, symbol ''χ'', is a chemical property that describes the tendency of an atom to attract a shared pair of electrons (or electron density) towards itself.
The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state.
A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy.
Epilepsy is a group of neurological disorders characterized by epileptic seizures.
Erongo is one of the 14 regions of Namibia, its capital is Swakopmund.
In chemistry, an ester is a chemical compound derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group.
Etching is traditionally the process of using strong acid or mordant to cut into the unprotected parts of a metal surface to create a design in intaglio (incised) in the metal.
Ethanol, also called alcohol, ethyl alcohol, grain alcohol, and drinking alcohol, is a chemical compound, a simple alcohol with the chemical formula.
Ethylene oxide, called oxirane by IUPAC, is an organic compound with the formula. It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of silver catalyst. The reactivity that is responsible for many of ethylene oxide's hazards also make it useful. Although too dangerous for direct household use and generally unfamiliar to consumers, ethylene oxide is used for making many consumer products as well as non-consumer chemicals and intermediates. These products include detergents, thickeners, solvents, plastics, and various organic chemicals such as ethylene glycol, ethanolamines, simple and complex glycols, polyglycol ethers, and other compounds. Although it is a vital raw material with diverse applications, including the manufacture of products like polysorbate 20 and polyethylene glycol (PEG) that are often more effective and less toxic than alternative materials, ethylene oxide itself is a very hazardous substance. At room temperature it is a flammable, carcinogenic, mutagenic, irritating, and anaesthetic gas. As a toxic gas that leaves no residue on items it contacts, ethylene oxide is a surface disinfectant that is widely used in hospitals and the medical equipment industry to replace steam in the sterilization of heat-sensitive tools and equipment, such as disposable plastic syringes. It is so flammable and extremely explosive that it is used as a main component of thermobaric weapons; therefore, it is commonly handled and shipped as a refrigerated liquid to control its hazardous nature.Rebsdat, Siegfried and Mayer, Dieter (2005) "Ethylene Oxide" in Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim..
Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline, petrol, biodiesel blends, diesel fuel, fuel oil, or coal.
An explosive material, also called an explosive, is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure.
In the field of physics, a Feshbach resonance, named after Herman Feshbach, is a feature of many-body systems in which a bound state is achieved if the coupling(s) between at least one internal degree of freedom and the reaction coordinates, which lead to dissociation, vanish.
Field-emission electric propulsion (FEEP) is an advanced electrostatic space propulsion concept, a form of ion thruster, that uses liquid metal (usually either caesium, indium or mercury) as a propellant.
Nuclear fission splits a heavy nucleus such as uranium or plutonium into two lighter nuclei, which are called fission products.
A flare, also sometimes called a fusee, is a type of pyrotechnic that produces a brilliant light or intense heat without an explosion.
Flerovium is a superheavy artificial chemical element with symbol Fl and atomic number 114.
A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light.
Formate (IUPAC name: methanoate) is the anion derived from formic acid.
Formic acid, systematically named methanoic acid, is the simplest carboxylic acid.
In chemistry, fractional crystallization is a method of refining substances based on differences in solubility.
Fractional crystallization, or crystal fractionation, is one of the most important geochemical and physical processes operating within the Earth's crust and mantle.
Francium is a chemical element with symbol Fr and atomic number 87.
Frequency is the number of occurrences of a repeating event per unit of time.
Gallium is a chemical element with symbol Ga and atomic number 31.
A gamma ray or gamma radiation (symbol γ or \gamma), is penetrating electromagnetic radiation arising from the radioactive decay of atomic nuclei.
The General Conference on Weights and Measures (Conférence générale des poids et mesures – CGPM) is the supreme authority of the International Bureau of Weights and Measures (Bureau international des poids et mesures – BIPM), the inter-governmental organization established in 1875 under the terms of the Metre Convention (Convention du Mètre) through which Member States act together on matters related to measurement science and measurement standards.
Germanium is a chemical element with symbol Ge and atomic number 32.
A getter is a deposit of reactive material that is placed inside a vacuum system, for the purpose of completing and maintaining the vacuum.
The Goiânia accident was a radioactive contamination accident that occurred on September 13, 1987, at Goiânia, in the Brazilian state of Goiás, after a forgotten radiotherapy source was taken from an abandoned hospital site in the city.
Gold is a chemical element with symbol Au (from aurum) and atomic number 79, making it one of the higher atomic number elements that occur naturally.
The ground state of a quantum mechanical system is its lowest-energy state; the energy of the ground state is known as the zero-point energy of the system.
Gustav Robert Kirchhoff (12 March 1824 – 17 October 1887) was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects.
Half-life (symbol t1⁄2) is the time required for a quantity to reduce to half its initial value.
A halide is a binary phase, of which one part is a halogen atom and the other part is an element or radical that is less electronegative (or more electropositive) than the halogen, to make a fluoride, chloride, bromide, iodide, astatide, or theoretically tennesside compound.
The halogens are a group in the periodic table consisting of five chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
Heart arrhythmia (also known as arrhythmia, dysrhythmia, or irregular heartbeat) is a group of conditions in which the heartbeat is irregular, too fast, or too slow.
The hertz (symbol: Hz) is the derived unit of frequency in the International System of Units (SI) and is defined as one cycle per second.
In crystallography, the hexagonal crystal family is one of the 6 crystal families, which includes 2 crystal systems (hexagonal and trigonal) and 2 lattice systems (hexagonal and rhombohedral).
HSAB concept is an initialism for "hard and soft (Lewis) acids and bases".
Hydrobromic acid is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water.
Hydrochloric acid is a colorless inorganic chemical system with the formula.
Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water.
Hydrogen is a chemical element with symbol H and atomic number 1.
Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the water cycle, water resources and environmental watershed sustainability.
Hygroscopy is the phenomenon of attracting and holding water molecules from the surrounding environment, which is usually at normal or room temperature.
In atomic physics, hyperfine structure refers to small shifts and splittings in the energy levels of atoms, molecules and ions, due to interaction between the state of the nucleus and the state of the electron clouds.
Hypokalemia, also spelled hypokalaemia, is a low level of potassium (K+) in the blood serum.
In petrology and geochemistry, an incompatible element is one that is unsuitable in size and/or charge to the cation sites of the minerals of which it is included.
Indium is a chemical element with symbol In and atomic number 49.
An inert gas/noble gas is a gas which does not undergo chemical reactions under a set of given conditions.
Infrared radiation (IR) is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore generally invisible to the human eye (although IR at wavelengths up to 1050 nm from specially pulsed lasers can be seen by humans under certain conditions). It is sometimes called infrared light.
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) involves the interaction of infrared radiation with matter.
An intermetallic (also called an intermetallic compound, intermetallic alloy, ordered intermetallic alloy, and a long-range-ordered alloy) is a solid-state compound exhibiting metallic bonding, defined stoichiometry and ordered crystal structure.
An internal standard in analytical chemistry is a chemical substance that is added in a constant amount to samples, the blank and calibration standards in a chemical analysis.
The International Atomic Energy Agency (IAEA) is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons.
The International Committee for Weights and Measures (abbreviated CIPM from the French Comité international des poids et mesures) consists of eighteen persons, each of a different nationality, from Member States of the Metre Convention (Convention du Mètre) appointed by the General Conference on Weights and Measures (CGPM) whose principal task is to promote worldwide uniformity in units of measurement by taking direct action or by submitting proposals to the CGPM.
The International System of Units (SI, abbreviated from the French Système international (d'unités)) is the modern form of the metric system, and is the most widely used system of measurement.
The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries.
An ion is an atom or molecule that has a non-zero net electrical charge (its total number of electrons is not equal to its total number of protons).
An ion thruster or ion drive is a form of electric propulsion used for spacecraft propulsion.
Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds.
Ionic radius, rion, is the radius of an atom's ion in ionic crystals structure.
The ionization energy (Ei) is qualitatively defined as the amount of energy required to remove the most loosely bound electron, the valence electron, of an isolated gaseous atom to form a cation.
Iron is a chemical element with symbol Fe (from ferrum) and atomic number 26.
Isotopes are variants of a particular chemical element which differ in neutron number.
Naturally occurring barium (56Ba) is a mix of six stable isotopes and one very long-lived radioactive primordial isotope, barium-130, recently identified as being unstable by geochemical means (from analysis of the presence of its daughter xenon-130 in rocks).
Caesium (55Cs; or cesium) has 40 known isotopes, making it, along with barium and mercury, the element with the most isotopes.
There are 37 known isotopes of iodine (53I) from 108I to 144I; all undergo radioactive decay except 127I, which is stable.
Naturally occurring xenon (54Xe) is made of eight stable isotopes and one very long-lived isotope.
The Journal of Chemical Education is a monthly peer-reviewed academic journal available in both print and electronic versions.
The Kramatorsk radiological accident was a radiation accident that happened in Kramatorsk, Ukrainian SSR from 1980 to 1989.
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.
Laser cooling refers to a number of techniques in which atomic and molecular samples are cooled down to near absolute zero.
Latin (Latin: lingua latīna) is a classical language belonging to the Italic branch of the Indo-European languages.
Leaching is a process where ore is soluble and impurities are insoluble, widely used extractive metallurgy technique which converts metals into soluble salts in aqueous media.
Lead is a chemical element with symbol Pb (from the Latin plumbum) and atomic number 82.
Lepidolite is a lilac-gray or rose-colored member of the mica group of minerals with formula K(Li,Al,Rb)2(Al,Si)4O10(F,OH)2.
A Lewis acid is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct.
, 118 chemical elements are identified.
Lithium (from lit) is a chemical element with symbol Li and atomic number 3.
The Lockheed SR-71 "Blackbird" is a long-range, Mach 3+ strategic reconnaissance aircraft that was operated by the United States Air Force.
Long-lived fission products (LLFPs) are radioactive materials with a long half-life (more than 200,000 years) produced by nuclear fission of uranium and plutonium.
Louis Essen FRS O.B.E. (6 September 1908 – 24 August 1997) was an English physicist whose most notable achievements were in the precise measurement of time and the determination of the speed of light.
Lustre or luster is the way light interacts with the surface of a crystal, rock, or mineral.
Magnesium is a chemical element with symbol Mg and atomic number 12.
A magnetohydrodynamic generator (MHD generator) is a magnetohydrodynamic converter that transforms thermal energy and kinetic energy into electricity.
A magnetometer is an instrument that measures magnetism—either the magnetization of a magnetic material like a ferromagnet, or the direction, strength, or relative change of a magnetic field at a particular location.
Manitoba is a province at the longitudinal centre of Canada.
The mass number (symbol A, from the German word Atomgewichte (atomic weight), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It determines the atomic mass of atoms. Because protons and neutrons both are baryons, the mass number A is identical with the baryon number B as of the nucleus as of the whole atom or ion. The mass number is different for each different isotope of a chemical element. This is not the same as the atomic number (Z) which denotes the number of protons in a nucleus, and thus uniquely identifies an element. Hence, the difference between the mass number and the atomic number gives the number of neutrons (N) in a given nucleus:. The mass number is written either after the element name or as a superscript to the left of an element's symbol. For example, the most common isotope of carbon is carbon-12, or, which has 6 protons and 6 neutrons. The full isotope symbol would also have the atomic number (Z) as a subscript to the left of the element symbol directly below the mass number:. This is technically redundant, as each element is defined by its atomic number, so it is often omitted.
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a measure of the lethal dose of a toxin, radiation, or pathogen.
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid at atmospheric pressure.
Mercury is a chemical element with symbol Hg and atomic number 80.
A metal (from Greek μέταλλον métallon, "mine, quarry, metal") is a material (an element, compound, or alloy) that is typically hard when in solid state, opaque, shiny, and has good electrical and thermal conductivity.
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are called alloys.
Methanol, also known as methyl alcohol among others, is a chemical with the formula CH3OH (a methyl group linked to a hydroxyl group, often abbreviated MeOH).
Methyl methacrylate (MMA) is an organic compound with the formula CH2.
The metre (British spelling and BIPM spelling) or meter (American spelling) (from the French unit mètre, from the Greek noun μέτρον, "measure") is the base unit of length in some metric systems, including the International System of Units (SI).
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; with frequencies between and.
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum.
Mineral water is water from a mineral spring that contains various minerals, such as salts and sulfur compounds.
Molar concentration (also called molarity, amount concentration or substance concentration) is a measure of the concentration of a chemical species, in particular of a solute in a solution, in terms of amount of substance per unit volume of solution.
Molybdenum is a chemical element with symbol Mo and atomic number 42.
n-Butyllithium (abbreviated n-BuLi) is an organolithium reagent.
Namibia, officially the Republic of Namibia (German:; Republiek van Namibië), is a country in southern Africa whose western border is the Atlantic Ocean.
A nanosecond (ns) is an SI unit of time equal to one thousand-millionth of a second (or one billionth of a second), that is, 1/1,000,000,000 of a second, or 10 seconds.
The National Physical Laboratory (NPL) is the national measurement standards laboratory for the United Kingdom, based at Bushy Park in Teddington, London, England.
Nature is a British multidisciplinary scientific journal, first published on 4 November 1869.
Neutron capture is a nuclear reaction in which an atomic nucleus and one or more neutrons collide and merge to form a heavier nucleus.
In applications such as nuclear reactors, a neutron poison (also called a neutron absorber or a nuclear poison) is a substance with a large neutron absorption cross-section.
Nickel is a chemical element with symbol Ni and atomic number 28.
Night vision is the ability to see in low-light conditions.
Publius Nigidius Figulus (c. 98 – 45 BC) was a scholar of the Late Roman Republic and one of the praetors for 58 BC.
Nitrate is a polyatomic ion with the molecular formula and a molecular mass of 62.0049 u.
Non-stoichiometric compounds are chemical compounds, almost always solid inorganic compounds, having elemental composition whose proportions cannot be represented by integers; most often, in such materials, some small percentage of atoms are missing or too many atoms are packed into an otherwise perfect lattice work.
Nuclear fallout, or simply fallout, is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and the shock wave have passed.
In nuclear physics and nuclear chemistry, nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei).
Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission.
The nuclear fuel cycle, also called nuclear fuel chain, is the progression of nuclear fuel through a series of differing stages.
A nuclear isomer is a metastable state of an atomic nucleus caused by the excitation of one or more of its nucleons (protons or neutrons).
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a magnetic field absorb and re-emit electromagnetic radiation.
A nuclear reactor, formerly known as an atomic pile, is a device used to initiate and control a self-sustained nuclear chain reaction.
Nuclear weapons tests are experiments carried out to determine the effectiveness, yield, and explosive capability of nuclear weapons.
Nucleic acids are biopolymers, or small biomolecules, essential to all known forms of life.
In chemistry and physics, a nucleon is either a proton or a neutron, considered in its role as a component of an atomic nucleus.
An oil well is a boring in the Earth that is designed to bring petroleum oil hydrocarbons to the surface.
Optical character recognition (also optical character reader, OCR) is the mechanical or electronic conversion of images of typed, handwritten or printed text into machine-encoded text, whether from a scanned document, a photo of a document, a scene-photo (for example the text on signs and billboards in a landscape photo) or from subtitle text superimposed on an image (for example from a television broadcast).
An optical fiber or optical fibre is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
In cell biology, an organelle is a specialized subunit within a cell that has a specific function, in which their function is vital for the cell to live.
Organic chemistry is a chemistry subdiscipline involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds.
Organofluorine chemistry describes the chemistry of the organofluorines, organic compounds that contain the carbon–fluorine bond.
The ounce (abbreviated oz; apothecary symbol: ℥) is a unit of mass, weight, or volume used in most British derived customary systems of measurement.
Oxalate (IUPAC: ethanedioate) is the dianion with the formula, also written.
The Oxford English Dictionary (OED) is the main historical dictionary of the English language, published by the Oxford University Press.
An oxide is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula.
In chemistry, an oxidizing agent (oxidant, oxidizer) is a substance that has the ability to oxidize other substances — in other words to cause them to lose electrons.
Oxygen is a chemical element with symbol O and atomic number 8.
Ozonide is the unstable, reactive polyatomic anion analog of ozone or any of several classes of organic organic peroxide compounds similar formed by the reaction of ozone with an unsaturated compound.
In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
A pegmatite is a holocrystalline, intrusive igneous rock composed of interlocking phaneritic crystals usually larger than 2.5 cm in size (1 in); such rocks are referred to as pegmatitic.
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trends.
Periodic trends are specific patterns that are present in the periodic table that illustrate different aspects of a certain element, including its radius and its electronic properties.
The Periodic Table of Videos (usually shortened to Periodic Videos) is a series of videos about chemical elements and the periodic table.
Peroxide is a compound with the structure R-O-O-R. The O−O group in a peroxide is called the peroxide group or peroxo group.
Petalite, also known as castorite, is a lithium aluminium tectosilicate mineral LiAlSi4O10, crystallizing in the monoclinic system.
Pezzottaite, marketed under the name raspberyl or raspberry beryl, is a newly identified mineral species, first recognized by the International Mineralogical Association in September 2003.
A phosphate is chemical derivative of phosphoric acid.
The photoelectric effect is the emission of electrons or other free carriers when light shines on a material.
Photomultiplier tubes (photomultipliers or PMTs for short), members of the class of vacuum tubes, and more specifically vacuum phototubes, are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum.
Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light.
Phthalic anhydride is the organic compound with the formula C6H4(CO)2O.
Physical Review Letters (PRL), established in 1958, is a peer-reviewed, scientific journal that is published 52 times per year by the American Physical Society.
The picometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: pm) or picometer (American spelling) is a unit of length in the metric system, equal to, or one trillionth of a metre, which is the SI base unit of length.
Plasma oscillations, also known as Langmuir waves (after Irving Langmuir), are rapid oscillations of the electron density in conducting media such as plasmas or metals in the ultraviolet region.
Platinum is a chemical element with symbol Pt and atomic number 78.
Pollucite is a zeolite mineral with the formula (Cs,Na)2Al2Si4O12·2H2O with iron, calcium, rubidium and potassium as common substituting elements.
In polymer chemistry, polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks.
Potassium is a chemical element with symbol K (from Neo-Latin kalium) and atomic number 19.
Potassium chloride (KCl) is a metal halide salt composed of potassium and chlorine.
In geometry, crystallography, mineralogy, and solid state physics, a primitive cell is a minimum volume cell (a unit cell) corresponding to a single lattice point of a structure with discrete translational symmetry.
The International Committee for Weights and Measures (CIPM) has proposed revised definitions of the SI base units, for consideration at the 26th General Conference on Weights and Measures (CGPM).
The pseudohalogens are polyatomic analogues of halogens, whose chemistry, resembling that of the true halogens, allows them to substitute for halogens in several classes of chemical compounds.
A pyrophoric substance (from Greek πυροφόρος, pyrophoros, "fire-bearing") ignites spontaneously in air at or below 55 °C (130 °F).
A pyrotechnic colorant is a chemical compound which causes a flame to burn with a particular color.
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
Quantum technology is a new field of physics and engineering, which transitions some of the properties of quantum mechanics, especially quantum entanglement, quantum superposition and quantum tunnelling, into practical applications such as quantum computing, quantum sensors, quantum cryptography, quantum simulation, quantum metrology and quantum imaging.
The rapid neutron-capture process, or so-called r-process, is a set of nuclear reactions that in nuclear astrophysics is responsible for the creation (nucleosynthesis) of approximately half the abundances of the atomic nuclei heavier than iron, usually synthesizing the entire abundance of the two most neutron-rich stable isotopes of each heavy element.
Radar cross-section (RCS) is a measure of how detectable an object is by radar.
Radiation therapy or radiotherapy, often abbreviated RT, RTx, or XRT, is therapy using ionizing radiation, generally as part of cancer treatment to control or kill malignant cells and normally delivered by a linear accelerator.
Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation, such as an alpha particle, beta particle with neutrino or only a neutrino in the case of electron capture, gamma ray, or electron in the case of internal conversion.
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is an atom that has excess nuclear energy, making it unstable.
The Rankine cycle is a model used to predict the performance of steam turbine systems.
A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
Relative atomic mass (symbol: A) or atomic weight is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to one unified atomic mass unit.
Relativistic quantum chemistry combines relativistic mechanics with quantum chemistry to explain elemental properties and structure, especially for the heavier elements of the periodic table.
Robert Wilhelm Eberhard Bunsen (30 March 1811N1 – 16 August 1899) was a German chemist.
Colloquially, room temperature is the range of air temperatures that most people prefer for indoor settings, which feel comfortable when wearing typical indoor clothing.
Rubidium is a chemical element with symbol Rb and atomic number 37.
Rubidium chloride is the chemical compound with the formula RbCl.
The slow neutron-capture process or s-process is a series of reactions in nuclear astrophysics that occur in stars, particularly AGB stars.
A scintillation counter is an instrument for detecting and measuring ionizing radiation by using the excitation effect of incident radiation on a scintillator material, and detecting the resultant light pulses.
A scintillator is a material that exhibits scintillation—the property of luminescence, when excited by ionizing radiation.
The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.
Secondary-ion mass spectrometry (SIMS) is a technique used to analyze the composition of solid surfaces and thin films by sputtering the surface of the specimen with a focused primary ion beam and collecting and analyzing ejected secondary ions.
Selenium is a chemical element with symbol Se and atomic number 34.
A semiconductor material has an electrical conductivity value falling between that of a conductor – such as copper, gold etc.
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula, where 0 ≤ x Silicate anions are often large polymeric molecules with an extense variety of structures, including chains and rings (as in polymeric metasilicate), double chains (as in, and sheets (as in. In geology and astronomy, the term silicate is used to mean silicate minerals, ionic solids with silicate anions; as well as rock types that consist predominantly of such minerals. In that context, the term also includes the non-ionic compound silicon dioxide (silica, quartz), which would correspond to x.
Silicon is a chemical element with symbol Si and atomic number 14.
Silver is a chemical element with symbol Ag (from the Latin argentum, derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47.
Sodium is a chemical element with symbol Na (from Latin natrium) and atomic number 11.
Sodium amide, commonly called sodamide, is the inorganic compound with the formula NaNH2.
Sodium chloride, also known as salt, is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions.
A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.
Solubility is the property of a solid, liquid or gaseous chemical substance called solute to dissolve in a solid, liquid or gaseous solvent.
Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites.
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.
In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength.
Spectroscopy is the study of the interaction between matter and electromagnetic radiation.
Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant).
In quantum mechanics and particle physics, spin is an intrinsic form of angular momentum carried by elementary particles, composite particles (hadrons), and atomic nuclei.
In fungi, the sporocarp (also known as fruiting body, fruit body or fruitbody) is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne.
Stable nuclides are nuclides that are not radioactive and so (unlike radionuclides) do not spontaneously undergo radioactive decay.
Sterilization (or sterilisation) refers to any process that eliminates, removes, kills, or deactivates all forms of life and other biological agents (such as fungi, bacteria, viruses, spore forms, prions, unicellular eukaryotic organisms such as Plasmodium, etc.) present in a specified region, such as a surface, a volume of fluid, medication, or in a compound such as biological culture media.
Stoichiometry is the calculation of reactants and products in chemical reactions.
Strontium-90 is a radioactive isotope of strontium produced by nuclear fission, with a half-life of 28.8 years.
Styrene, also known as ethenylbenzene, vinylbenzene, and phenylethene, is an organic compound with the chemical formula C6H5CH.
Suboxides are a class of oxides wherein the electropositive element is in excess relative to the “normal” oxides.
The sulfate or sulphate (see spelling differences) ion is a polyatomic anion with the empirical formula.
Sulfur or sulphur is a chemical element with symbol S and atomic number 16.
Sulfur dioxide (also sulphur dioxide in British English) is the chemical compound with the formula.
Sulfur trioxide (alternative spelling sulphur trioxide) is the chemical compound with the formula SO3.
Sulfuric acid (alternative spelling sulphuric acid) is a mineral acid with molecular formula H2SO4.
A supernova (plural: supernovae or supernovas, abbreviations: SN and SNe) is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion.
A superoxide is a compound that contains the superoxide anion, which has the chemical formula.
Sylvite, or sylvine, is potassium chloride (KCl) in natural mineral form.
Tanco Mine is an underground caesium and tantalum mine, owned and operated by Cabot Corporation on the north west shore of Bernic Lake, Manitoba, Canada.
Tantalum is a chemical element with symbol Ta and atomic number 73.
Tellurium is a chemical element with symbol Te and atomic number 52.
A thermionic converter consists of a hot electrode which thermionically emits electrons over a potential energy barrier to a cooler electrode, producing a useful electric power output.
Thorium is a weakly radioactive metallic chemical element with symbol Th and atomic number 90.
Tin is a chemical element with the symbol Sn (from stannum) and atomic number 50.
The tonne (Non-SI unit, symbol: t), commonly referred to as the metric ton in the United States, is a non-SI metric unit of mass equal to 1,000 kilograms;.
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism.
Toxicology and Applied Pharmacology is a scientific journal for original research pertaining to action of chemicals, drugs, or natural products to animals or humans.
Trifluoroacetic acid (TFA) is an organofluorine compound with the chemical formula CF3CO2H.
Tritium (or; symbol or, also known as hydrogen-3) is a radioactive isotope of hydrogen.
Tungsten, or wolfram, is a chemical element with symbol W (referring to wolfram) and atomic number 74.
Ultracold atoms are atoms that are maintained at temperatures close to 0 kelvin (absolute zero), typically below temperatures of some tenths of microkelvins (µK).
Uranium is a chemical element with symbol U and atomic number 92.
In electronics, a vacuum tube, an electron tube, or just a tube (North America), or valve (Britain and some other regions) is a device that controls electric current between electrodes in an evacuated container.
The video camera tube was a type of cathode ray tube used to capture the television image prior to the introduction of charge-coupled devices (CCDs) in the 1980s.
A virus is a small infectious agent that replicates only inside the living cells of other organisms.
Well logging, also known as borehole logging is the practice of making a detailed record (a well log) of the geologic formations penetrated by a borehole.
X-rays make up X-radiation, a form of electromagnetic radiation.
Xenon is a chemical element with symbol Xe and atomic number 54.
Xenon-135 (135Xe) is an unstable isotope of xenon with a half-life of about 9.2 hours.
Zimbabwe, officially the Republic of Zimbabwe, is a landlocked country located in southern Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa, Botswana, Zambia and Mozambique. The capital and largest city is Harare. A country of roughly million people, Zimbabwe has 16 official languages, with English, Shona, and Ndebele the most commonly used. Since the 11th century, present-day Zimbabwe has been the site of several organised states and kingdoms as well as a major route for migration and trade. The British South Africa Company of Cecil Rhodes first demarcated the present territory during the 1890s; it became the self-governing British colony of Southern Rhodesia in 1923. In 1965, the conservative white minority government unilaterally declared independence as Rhodesia. The state endured international isolation and a 15-year guerrilla war with black nationalist forces; this culminated in a peace agreement that established universal enfranchisement and de jure sovereignty as Zimbabwe in April 1980. Zimbabwe then joined the Commonwealth of Nations, from which it was suspended in 2002 for breaches of international law by its then government and from which it withdrew from in December 2003. It is a member of the United Nations, the Southern African Development Community (SADC), the African Union (AU), and the Common Market for Eastern and Southern Africa (COMESA). It was once known as the "Jewel of Africa" for its prosperity. Robert Mugabe became Prime Minister of Zimbabwe in 1980, when his ZANU-PF party won the elections following the end of white minority rule; he was the President of Zimbabwe from 1987 until his resignation in 2017. Under Mugabe's authoritarian regime, the state security apparatus dominated the country and was responsible for widespread human rights violations. Mugabe maintained the revolutionary socialist rhetoric of the Cold War era, blaming Zimbabwe's economic woes on conspiring Western capitalist countries. Contemporary African political leaders were reluctant to criticise Mugabe, who was burnished by his anti-imperialist credentials, though Archbishop Desmond Tutu called him "a cartoon figure of an archetypal African dictator". The country has been in economic decline since the 1990s, experiencing several crashes and hyperinflation along the way. On 15 November 2017, in the wake of over a year of protests against his government as well as Zimbabwe's rapidly declining economy, Mugabe was placed under house arrest by the country's national army in a coup d'état. On 19 November 2017, ZANU-PF sacked Robert Mugabe as party leader and appointed former Vice President Emmerson Mnangagwa in his place. On 21 November 2017, Mugabe tendered his resignation prior to impeachment proceedings being completed.
Zinc bromide (ZnBr2) is an inorganic compound with the chemical formula ZnBr2.
Zirconium is a chemical element with symbol Zr and atomic number 40.