210 relations: Académie française, Acid, Acid strength, Adipose tissue, Alchemy, Aliphatic compound, Alpha particle, Antoine Jérôme Balard, Aromaticity, Arthritis, Astatine, Bacteria, Bernard Courtois, Beta decay, Bismuth, Bleach, Boiling point, Bracket, Brain, Brine, Bromine, Calcium fluoride, Carl Wilhelm Scheele, Carnallite, Celsius, Chemical burn, Chemical compound, Chemical element, Chemical equilibrium, Chemical warfare, Chemist, China, Chlorine, Chlorine-36, Cluster decay, Cod as food, Committee on Data for Science and Technology, Corrosive substance, Covalent bond, Covalent radius, Dale R. Corson, Density, Dental fluorosis, Diatomic molecule, Disinfectant, Drug discovery, Dry weight, Edible mushroom, Effective nuclear charge, Electrolysis, ..., Electronegativity, Emilio Segrè, Epidermis, Flame retardant, Fluorine, Fluorite, Flux (metallurgy), Fred Allison, Fused quartz, Gamma-Aminobutyric acid, George Gore (electrochemist), Gland, Greek language, Group (periodic table), Halite, Halocarbon, Halogen bond, Halogen lamp, Henri Moissan, Herbert Henry Dow, Herring as food, Homonuclear molecule, Horia Hulubei, Humphry Davy, Hydrochloric acid, Hydrofluoric acid, Hydrogen astatide, Hydrogen bond, Hydrogen bromide, Hydrogen chloride, Hydrogen fluoride, Hydrogen halide, Hydrogen iodide, Hypobromous acid, Hypochlorous acid, Immune system, Incandescent light bulb, Industry, Intellectual disability, Interhalogen, International Union of Pure and Applied Chemistry, Iodate, Iodine, Iodine heptafluoride, Iodine-129, Ionization energy, Iron(II) iodide, Iron(III) bromide, Iron(III) chloride, Iron(III) fluoride, Irritation, Isotope, Isotopes of astatine, Isotopes of bromine, Isotopes of chlorine, Isotopes of fluorine, Isotopes of iodine, Isotopes of protactinium, Israel, Japan, Jöns Jacob Berzelius, Johann Schweigger, Joseph Louis Gay-Lussac, Joule per mole, Journal of Chemical Physics, Kelp, Kelvin, Kenneth Ross MacKenzie, Latin, Lipid bilayer, Lipophilicity, Lobster, London dispersion force, Manganese dioxide, Mass number, Melting point, Microorganism, Mineral, Molecule, National Institute of Standards and Technology, Natural gas, Neptunium, Niter, Nitrate, Noble gas, Nucleophilic abstraction, Nuclide, Octet rule, Organic compound, Organism, Organobromine compound, Organofluorine chemistry, Organoiodine compound, Oxygen, Oyster, Paper, Perfluorinated compound, Periodic table, Periodic trends, Phosphoric acid, Picometre, Plastic, Plutonium, Polonium, Polybrominated diphenyl ethers, Polychlorinated biphenyl, Polyhalogenated compound, Polymer, Polytetrafluoroethylene, Potassium bifluoride, Potassium chloride, Potassium iodide, Potato, Pseudohalogen, Pulmonary edema, Pure and Applied Chemistry, Radioactive decay, Reactivity (chemistry), Relative atomic mass, Russia, Salt (chemistry), Seaweed, Shrimp and prawn as food, Significant figures, Silicon tetrafluoride, Silver bromide, Skeletal fluorosis, Sodium bromide, Sodium chloride, Sodium fluoride, Sodium hypochlorite, Sodium iodide, Soil, Spallation, Spectroscopy, Standard conditions for temperature and pressure, State of matter, Sterilization (microbiology), Stomach, Sulfur dioxide, Sulfuric acid, Sunflower seed, Sweden, Sylvite, Tennessee, Tennessine, Textile, Thyroid, Thyroid hormones, Tooth decay, Triiodide, Tungsten, Unified atomic mass unit, United States, Uranium, Walter Minder, Water fluoridation, Watt, World War I, Yvette Cauchois. Expand index (160 more) » « Shrink index
The Académie française is the pre-eminent French council for matters pertaining to the French language.
An acid is a molecule or ion capable of donating a hydron (proton or hydrogen ion H+), or, alternatively, capable of forming a covalent bond with an electron pair (a Lewis acid).
The strength of an acid refers to its ability or tendency to lose a proton (H+).
In biology, adipose tissue, body fat, or simply fat is a loose connective tissue composed mostly of adipocytes.
Alchemy is a philosophical and protoscientific tradition practiced throughout Europe, Africa, Brazil and Asia.
In organic chemistry, hydrocarbons (compounds composed of carbon and hydrogen) are divided into two classes: aromatic compounds and aliphatic compounds (G. aleiphar, fat, oil) also known as non-aromatic compounds.
Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus.
Antoine Jérôme Balard (30 September 180230 April 1876) was a French chemist and one of the discoverers of bromine.
In organic chemistry, the term aromaticity is used to describe a cyclic (ring-shaped), planar (flat) molecule with a ring of resonance bonds that exhibits more stability than other geometric or connective arrangements with the same set of atoms.
Arthritis is a term often used to mean any disorder that affects joints.
Astatine is a radioactive chemical element with symbol At and atomic number 85.
Bacteria (common noun bacteria, singular bacterium) is a type of biological cell.
Bernard Courtois, also spelled Barnard Courtois, (8 February 1777 – 27 September 1838) was a French chemist credited with first isolating iodine and morphine.
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.
Bismuth is a chemical element with symbol Bi and atomic number 83.
Bleach is the generic name for any chemical product which is used industrially and domestically to whiten clothes, lighten hair color and remove stains.
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.
A bracket is a tall punctuation mark typically used in matched pairs within text, to set apart or interject other text.
The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals.
Brine is a high-concentration solution of salt (usually sodium chloride) in water.
Bromine is a chemical element with symbol Br and atomic number 35.
Calcium fluoride is the inorganic compound of the elements calcium and fluorine with the formula CaF2.
Carl Wilhelm Scheele (9 December 1742 – 21 May 1786) was a Swedish Pomeranian and German pharmaceutical chemist.
Carnallite (also carnalite) is an evaporite mineral, a hydrated potassium magnesium chloride with formula KMgCl3·6(H2O).
The Celsius scale, previously known as the centigrade scale, is a temperature scale used by the International System of Units (SI).
A chemical burn occurs when living tissue is exposed to a corrosive substance such as a strong acid or base.
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) composed of atoms from more than one element held together by chemical bonds.
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).
In a chemical reaction, chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system.
Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons.
A chemist (from Greek chēm (ía) alchemy; replacing chymist from Medieval Latin alchimista) is a scientist trained in the study of chemistry.
China, officially the People's Republic of China (PRC), is a unitary one-party sovereign state in East Asia and the world's most populous country, with a population of around /1e9 round 3 billion.
Chlorine is a chemical element with symbol Cl and atomic number 17.
Chlorine-36 is an isotope of chlorine.
Cluster decay, also named heavy particle radioactivity or heavy ion radioactivity, is a type of nuclear decay in which an atomic nucleus emits a small "cluster" of neutrons and protons, more than in an alpha particle, but less than a typical binary fission fragment.
This article is about cod and other cod-like fishes from the family of Gadidae, such as haddock, pollock and whiting, regarded as food.
The Committee on Data for Science and Technology (CODATA) was established in 1966 as an interdisciplinary committee of the International Council for Science.
A corrosive substance is one that will destroy and damage other substances with which it comes into contact.
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms.
The covalent radius, rcov, is a measure of the size of an atom that forms part of one covalent bond.
Dale Raymond Corson (April 5, 1914 – March 31, 2012) was the eighth president of Cornell University.
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume.
Dental fluorosis (also termed mottled enamel) is an extremely common disorder, characterized by hypomineralization of tooth enamel caused by ingestion of excessive fluoride during enamel formation.
Diatomic molecules are molecules composed of only two atoms, of the same or different chemical elements.
Disinfectants are antimicrobial agents that are applied to the surface of non-living objects to destroy microorganisms that are living on the objects.
In the fields of medicine, biotechnology and pharmacology, drug discovery is the process by which new candidate medications are discovered.
Dry weight is the weight of a vehicle without any consumables, passengers, or cargo.
Edible mushrooms are the fleshy and edible fruit bodies of several species of macrofungi (fungi which bear fruiting structures that are large enough to be seen with the naked eye).
The effective nuclear charge (often symbolized as Z_ or Z^\ast) is the net positive charge experienced by an electron in a polyelectronic atom.
In chemistry and manufacturing, electrolysis is a technique that uses a direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction.
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.
Emilio Gino Segrè (1 February 1905 – 22 April 1989) was an Italian-American physicist and Nobel laureate, who discovered the elements technetium and astatine, and the antiproton, a subatomic antiparticle, for which he was awarded the Nobel Prize in Physics in 1959.
The epidermis is the outer layer of the three layers that make up the skin, the inner layers being the dermis and hypodermis.
The term flame retardants subsumes a diverse group of chemicals which are added to manufactured materials, such as plastics and textiles, and surface finishes and coatings.
Fluorine is a chemical element with symbol F and atomic number 9.
Not to be confused with Fluoride. Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2.
In metallurgy, a flux (derived from Latin fluxus meaning “flow”) is a chemical cleaning agent, flowing agent, or purifying agent.
Fred C. Allison (July 4, 1882 – August 2, 1974) was an American physicist.
Fused quartz or fused silica is glass consisting of silica in amorphous (non-crystalline) form.
gamma-Aminobutyric acid, or γ-aminobutyric acid, or GABA, is the chief inhibitory neurotransmitter in the mammalian central nervous system.
George Gore (22 January 1826 – 20 December 1908) was an English electrochemist.
A gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland).
Greek (Modern Greek: ελληνικά, elliniká, "Greek", ελληνική γλώσσα, ellinikí glóssa, "Greek language") is an independent branch of the Indo-European family of languages, native to Greece and other parts of the Eastern Mediterranean and the Black Sea.
In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements.
Halite, commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride (NaCl).
Halocarbon compounds are chemicals in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms (fluorine, chlorine, bromine or iodine –) resulting in the formation of organofluorine compounds, organochlorine compounds, organobromine compounds, and organoiodine compounds.
A halogen bond occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a halogen atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity.
A halogen lamp, also known as a tungsten halogen, quartz-halogen or quartz iodine lamp, is an incandescent lamp consisting of a tungsten filament sealed into a compact transparent envelope that is filled with a mixture of an inert gas and a small amount of a halogen such as iodine or bromine.
Ferdinand Frederick Henri Moissan (28 September 1852 – 20 February 1907) was a French chemist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds.
Herbert Henry Dow (February 26, 1866 – October 15, 1930) was a Canadian-born American chemical industrialist, best known as the founder of the American multinational conglomerate Dow Chemical.
Herrings are forage fish, mostly belonging to the family Clupeidae.
Homonuclear molecules, or homonuclear species, are molecules composed of only one type of element.
Horia Hulubei (15 November 1896 – 22 November 1972) was a Romanian nuclear physicist, known for his contributions to the development of X-ray spectroscopy.
Sir Humphry Davy, 1st Baronet (17 December 177829 May 1829) was a Cornish chemist and inventor, who is best remembered today for isolating, using electricity, a series of elements for the first time: potassium and sodium in 1807 and calcium, strontium, barium, magnesium and boron the following year, as well as discovering the elemental nature of chlorine and iodine.
Hydrochloric acid is a colorless inorganic chemical system with the formula.
Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water.
Hydrogen astatide, also known as astatine hydride, astatane, or astidohydrogen, is a chemical compound with the chemical formula, consisting of an astatine atom covalently bonded to a hydrogen atom.
A hydrogen bond is a partially electrostatic attraction between a hydrogen (H) which is bound to a more electronegative atom such as nitrogen (N), oxygen (O), or fluorine (F), and another adjacent atom bearing a lone pair of electrons.
Hydrogen bromide is the diatomic molecule with the formula.
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide.
Hydrogen fluoride is a chemical compound with the chemical formula.
Hydrogen halides are diatomic inorganic compounds with the formula HX where X is one of the halogens: fluorine, chlorine, bromine, iodine, or astatine.
Hydrogen iodide is a diatomic molecule and hydrogen halide.
Hypobromous acid is a very weak and unstable acid with chemical formula of HOBr.
Hypochlorous acid (HClO) is a weak acid that forms when chlorine dissolves in water, and itself partially dissociates, forming ClO-.
The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease.
An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated to such a high temperature that it glows with visible light (incandescence).
Industry is the production of goods or related services within an economy.
Intellectual disability (ID), also known as general learning disability, and mental retardation (MR), is a generalized neurodevelopmental disorder characterized by significantly impaired intellectual and adaptive functioning.
An interhalogen compound is a molecule which contains two or more different halogen atoms (fluorine, chlorine, bromine, iodine, or astatine) and no atoms of elements from any other group.
The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries.
An iodate is a conjugate base of iodic acid.
Iodine is a chemical element with symbol I and atomic number 53.
Iodine heptafluoride, also known as iodine(VII) fluoride or iodine fluoride, is an interhalogen compound with the chemical formula IF7.
Iodine-129 (129I) is a long-lived radioisotope of iodine which occurs naturally, but also is of special interest in the monitoring and effects of man-made nuclear fission decay products, where it serves as both tracer and potential radiological contaminant.
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(II) iodide is an inorganic compound with the chemical formula FeI2.
Iron(III) bromide is the chemical compound with the formula FeBr3.
Iron(III) chloride, also called ferric chloride, is an industrial scale commodity chemical compound, with the formula FeCl3 and with iron in the +3 oxidation state.
Iron(III) fluoride, also known as ferric fluoride, is an inorganic compound.
Irritation, in biology and physiology, is a state of inflammation or painful reaction to allergy or cell-lining damage.
Isotopes are variants of a particular chemical element which differ in neutron number.
Astatine (85At) has 37 known isotopes, all of which are radioactive; the range of their mass numbers is from 191 to 229.
Bromine (35Br) has two stable isotopes, 79Br and 81Br, and 30 known radioisotopes, the most stable of which is 77Br, with a half-life of 57.036 hours.
Chlorine (17Cl) has 24 isotopes with mass numbers ranging from 28Cl to 51Cl and 2 isomers (34mCl and 38mCl).
Although fluorine (9F) has 18 known isotopes from 14F to 31F and two isomers (18mF and 26mF), only one of these isotopes is stable, that is, fluorine-19; as such, it is a monoisotopic element.
There are 37 known isotopes of iodine (53I) from 108I to 144I; all undergo radioactive decay except 127I, which is stable.
Protactinium (91Pa) has no stable isotopes.
Israel, officially the State of Israel, is a country in the Middle East, on the southeastern shore of the Mediterranean Sea and the northern shore of the Red Sea.
Japan (日本; Nippon or Nihon; formally 日本国 or Nihon-koku, lit. "State of Japan") is a sovereign island country in East Asia.
Baron Jöns Jacob Berzelius (20 August 1779 – 7 August 1848), named by himself and contemporary society as Jacob Berzelius, was a Swedish chemist.
Johann Salomo Christoph Schweigger (8 April 1779 – 6 September 1857) was a German chemist, physicist, and professor of mathematics born in Erlangen.
Joseph Louis Gay-Lussac (also Louis Joseph Gay-Lussac; 6 December 1778 – 9 May 1850) was a French chemist and physicist.
The joule per mole (symbol: J·mole−1 or J/mol) is an SI derived unit of energy per amount of material.
The Journal of Chemical Physics is a scientific journal published by the American Institute of Physics that carries research papers on chemical physics.
Kelps are large brown algae seaweeds that make up the order Laminariales.
The Kelvin scale is an absolute thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
Kenneth Ross MacKenzie (June 15, 1912 – July 4, 2002) together with Dale R. Corson and Emilio Segrè, synthesized the element astatine, in 1940.
Latin (Latin: lingua latīna) is a classical language belonging to the Italic branch of the Indo-European languages.
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules.
Lipophilicity (from Greek λίπος "fat" and φίλος "friendly"), refers to the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene.
Lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans.
London dispersion forces (LDF, also known as dispersion forces, London forces, instantaneous dipole–induced dipole forces, or loosely van der Waals forces) are a type of force acting between atoms and molecules.
Manganese(IV) oxide is the inorganic compound with the formula.
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.
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.
A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera and anthrax. Microorganisms include all unicellular organisms and so are extremely diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms. These were previously grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans. Some protists are related to animals and some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here. They live in almost every habitat from the poles to the equator, deserts, geysers, rocks and the deep sea. Some are adapted to extremes such as very hot or very cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms also make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45 billion year old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel, enzymes and other bioactive compounds. They are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora. They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures.
A mineral is a naturally occurring chemical compound, usually of crystalline form and not produced by life processes.
A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
The National Institute of Standards and Technology (NIST) is one of the oldest physical science laboratories in the United States.
Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly including varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.
Neptunium is a chemical element with symbol Np and atomic number 93.
Niter, or nitre (chiefly British), is the mineral form of potassium nitrate, KNO3, also known as saltpeter or saltpetre.
Nitrate is a polyatomic ion with the molecular formula and a molecular mass of 62.0049 u.
The noble gases (historically also the inert gases) make up a group of chemical elements with similar properties; under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity.
Nucleophilic abstraction is a type of an organometallic reaction which can be defined as a nucleophilic attack on a ligand which causes part or all of the original ligand to be removed from the metal along with the nucleophile.
A nuclide (from nucleus, also known as nuclear species) is an atomic species characterized by the specific constitution of its nucleus, i.e., by its number of protons Z, its number of neutrons N, and its nuclear energy state.
The octet rule is a chemical rule of thumb that reflects observation that atoms of main-group elements tend to combine in such a way that each atom has eight electrons in its valence shell, giving it the same electron configuration as a noble gas.
In chemistry, an organic compound is generally any chemical compound that contains carbon.
In biology, an organism (from Greek: ὀργανισμός, organismos) is any individual entity that exhibits the properties of life.
Organobromine compounds, also called organobromides, are organic compounds that contain carbon bonded to bromine.
Organofluorine chemistry describes the chemistry of the organofluorines, organic compounds that contain the carbon–fluorine bond.
Organoiodine compounds are organic compounds that contain one or more carbon–iodine bonds.
Oxygen is a chemical element with symbol O and atomic number 8.
Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats.
Paper is a thin material produced by pressing together moist fibres of cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets.
A perfluorinated compound (PFC) per- or polyfluoroalkyl chemical is an organofluorine compound containing only carbon-fluorine bonds (no C-H bonds) and C-C bonds but also other heteroatoms.
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.
Phosphoric acid (also known as orthophosphoric acid or phosphoric(V) acid) is a mineral (inorganic) and weak acid having the chemical formula H3PO4.
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.
Plastic is material consisting of any of a wide range of synthetic or semi-synthetic organic compounds that are malleable and so can be molded into solid objects.
Plutonium is a radioactive chemical element with symbol Pu and atomic number 94.
Polonium is a chemical element with symbol Po and atomic number 84.
Polybrominated diphenyl ethers or PBDEs, are organobromine compounds that are used as flame retardant.
A polychlorinated biphenyl (PCB) is an organic chlorine compound with the formula C12H10−xClx.
Polyhalogenated compounds (PHCs) are any compounds with multiple substitutions of halogens.
A polymer (Greek poly-, "many" + -mer, "part") is a large molecule, or macromolecule, composed of many repeated subunits.
Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications.
Potassium bifluoride is the inorganic compound with the formula KHF2.
Potassium chloride (KCl) is a metal halide salt composed of potassium and chlorine.
Potassium iodide is a chemical compound, medication, and dietary supplement.
The potato is a starchy, tuberous crop from the perennial nightshade Solanum tuberosum.
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.
Pulmonary edema is fluid accumulation in the tissue and air spaces of the lungs.
Pure and Applied Chemistry (abbreviated Pure Appl. Chem.) is the official journal for the International Union of Pure and Applied Chemistry (IUPAC).
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.
In chemistry, reactivity is the impetus for which a chemical substance undergoes a chemical reaction, either by itself or with other materials, with an overall release of energy.
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.
Russia (rɐˈsʲijə), officially the Russian Federation (p), is a country in Eurasia. At, Russia is the largest country in the world by area, covering more than one-eighth of the Earth's inhabited land area, and the ninth most populous, with over 144 million people as of December 2017, excluding Crimea. About 77% of the population live in the western, European part of the country. Russia's capital Moscow is one of the largest cities in the world; other major cities include Saint Petersburg, Novosibirsk, Yekaterinburg and Nizhny Novgorod. Extending across the entirety of Northern Asia and much of Eastern Europe, Russia spans eleven time zones and incorporates a wide range of environments and landforms. From northwest to southeast, Russia shares land borders with Norway, Finland, Estonia, Latvia, Lithuania and Poland (both with Kaliningrad Oblast), Belarus, Ukraine, Georgia, Azerbaijan, Kazakhstan, China, Mongolia and North Korea. It shares maritime borders with Japan by the Sea of Okhotsk and the U.S. state of Alaska across the Bering Strait. The East Slavs emerged as a recognizable group in Europe between the 3rd and 8th centuries AD. Founded and ruled by a Varangian warrior elite and their descendants, the medieval state of Rus arose in the 9th century. In 988 it adopted Orthodox Christianity from the Byzantine Empire, beginning the synthesis of Byzantine and Slavic cultures that defined Russian culture for the next millennium. Rus' ultimately disintegrated into a number of smaller states; most of the Rus' lands were overrun by the Mongol invasion and became tributaries of the nomadic Golden Horde in the 13th century. The Grand Duchy of Moscow gradually reunified the surrounding Russian principalities, achieved independence from the Golden Horde. By the 18th century, the nation had greatly expanded through conquest, annexation, and exploration to become the Russian Empire, which was the third largest empire in history, stretching from Poland on the west to Alaska on the east. Following the Russian Revolution, the Russian Soviet Federative Socialist Republic became the largest and leading constituent of the Union of Soviet Socialist Republics, the world's first constitutionally socialist state. The Soviet Union played a decisive role in the Allied victory in World War II, and emerged as a recognized superpower and rival to the United States during the Cold War. The Soviet era saw some of the most significant technological achievements of the 20th century, including the world's first human-made satellite and the launching of the first humans in space. By the end of 1990, the Soviet Union had the world's second largest economy, largest standing military in the world and the largest stockpile of weapons of mass destruction. Following the dissolution of the Soviet Union in 1991, twelve independent republics emerged from the USSR: Russia, Ukraine, Belarus, Kazakhstan, Uzbekistan, Armenia, Azerbaijan, Georgia, Kyrgyzstan, Moldova, Tajikistan, Turkmenistan and the Baltic states regained independence: Estonia, Latvia, Lithuania; the Russian SFSR reconstituted itself as the Russian Federation and is recognized as the continuing legal personality and a successor of the Soviet Union. It is governed as a federal semi-presidential republic. The Russian economy ranks as the twelfth largest by nominal GDP and sixth largest by purchasing power parity in 2015. Russia's extensive mineral and energy resources are the largest such reserves in the world, making it one of the leading producers of oil and natural gas globally. The country is one of the five recognized nuclear weapons states and possesses the largest stockpile of weapons of mass destruction. Russia is a great power as well as a regional power and has been characterised as a potential superpower. It is a permanent member of the United Nations Security Council and an active global partner of ASEAN, as well as a member of the G20, the Shanghai Cooperation Organisation (SCO), the Council of Europe, the Asia-Pacific Economic Cooperation (APEC), the Organization for Security and Co-operation in Europe (OSCE), and the World Trade Organization (WTO), as well as being the leading member of the Commonwealth of Independent States (CIS), the Collective Security Treaty Organization (CSTO) and one of the five members of the Eurasian Economic Union (EEU), along with Armenia, Belarus, Kazakhstan and Kyrgyzstan.
In chemistry, a salt is an ionic compound that can be formed by the neutralization reaction of an acid and a base.
Seaweed or macroalgae refers to several species of macroscopic, multicellular, marine algae.
Shrimp and prawn are important types of seafood that are consumed worldwide.
The significant figures (also known as the significant digits) of a number are digits that carry meaning contributing to its measurement resolution.
Silicon tetrafluoride or tetrafluorosilane is the chemical compound with the formula SiF4.
Silver bromide (AgBr), a soft, pale-yellow, water-insoluble salt well known (along with other silver halides) for its unusual sensitivity to light.
Skeletal fluorosis is a bone disease caused by excessive accumulation of fluoride in the bones.
Sodium bromide is an inorganic compound with the formula NaBr.
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.
Sodium fluoride (NaF) is an inorganic compound with the formula NaF.
Sodium iodide (chemical formula NaI) is an ionic compound formed from the chemical reaction of sodium metal and iodine.
Soil is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life.
Spallation is a process in which fragments of material (spall) are ejected from a body due to impact or stress.
Spectroscopy is the study of the interaction between matter and electromagnetic radiation.
Standard conditions for temperature and pressure are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data.
In physics, a state of matter is one of the distinct forms in which matter can exist.
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.
The stomach (from ancient Greek στόμαχος, stomachos, stoma means mouth) is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates.
Sulfur dioxide (also sulphur dioxide in British English) is the chemical compound with the formula.
Sulfuric acid (alternative spelling sulphuric acid) is a mineral acid with molecular formula H2SO4.
The sunflower seed is the fruit of the sunflower (Helianthus annuus).
Sweden (Sverige), officially the Kingdom of Sweden (Swedish), is a Scandinavian country in Northern Europe.
Sylvite, or sylvine, is potassium chloride (KCl) in natural mineral form.
Tennessee (translit) is a state located in the southeastern region of the United States.
Tennessine is a synthetic chemical element with symbol Ts and atomic number 117.
A textile is a flexible material consisting of a network of natural or artificial fibres (yarn or thread).
The thyroid gland, or simply the thyroid, is an endocrine gland in the neck, consisting of two lobes connected by an isthmus.
Thyroid hormones are two hormones produced and released by the thyroid gland, namely triiodothyronine (T3) and thyroxine (T4).
Tooth decay, also known as dental caries or cavities, is a breakdown of teeth due to acids made by bacteria.
In chemistry, triiodide usually refers to the triiodide ion,.
Tungsten, or wolfram, is a chemical element with symbol W (referring to wolfram) and atomic number 74.
The unified atomic mass unit or dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass).
The United States of America (USA), commonly known as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major self-governing territories, and various possessions.
Uranium is a chemical element with symbol U and atomic number 92.
Walter Minder (August 6, 1905 – April 1, 1992) was a Swiss mineralogist and chemist.
Water fluoridation is the controlled addition of fluoride to a public water supply to reduce tooth decay.
The watt (symbol: W) is a unit of power.
World War I (often abbreviated as WWI or WW1), also known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918.
Yvette Cauchois (19 December 1908 – 19 November 1999) was a French physicist known for her contributions to x-ray spectroscopy and x-ray optics, and for pioneering European synchrotron research.
Dihalo, Fluorine family, Fluorine group, Group 17, Group 17 element, Group 17 elements, Group 7A, Halide group, Hallogen, Halogen Element, Halogen Group, Halogen elements, Halogen group, Halogens, The halogens.