453 relations: Absorption band, Abundance of the chemical elements, Acetamide, Acetic acid, Acetic anhydride, Acetone, Acetylene, Acid, Adenosine triphosphate, Adhesive, Aerobic organism, Air pollution, Aircraft, Airglow, Alchemy, Alcohol, Aldehyde, Alexander von Humboldt, Allotropes of oxygen, Allotropy, Aluminium, Aluminium oxide, Ambient pressure, Amedeo Avogadro, American football, Amide, Anaerobic organism, Ancient Greece, Ancient Greek, Angewandte Chemie, Animal, Antibonding molecular orbital, Antifreeze, Antimony, Antoine Lavoisier, Apollo (spacecraft), Apollo 1, Archaea, Artery, Arthropod, Asphalt, ASTM International, Atmosphere of Earth, Atmospheric diving suit, Atomic mass, Atomic number, Atomic orbital, Auburn, Massachusetts, Aufbau principle, Aurora, ..., Autoxidation, Avogadro's law, Bacteria, Banded iron formation, Barbecue, Bauxite, Beta decay, Biochemical oxygen demand, Biogeochemical cycle, Biomolecule, Biosphere, Bohr effect, Bond order, Breathing, Breathing gas, Calcium, Calcium carbonate, California, Calx, Cambrian, Carbohydrate, Carbon, Carbon cycle, Carbon dioxide, Carbon monoxide, Carbon monoxide poisoning, Carboniferous, Carboxylic acid, Carl von Linde, Carl Wilhelm Scheele, Carotenoid, Cascade (chemical engineering), Cellular respiration, Celsius, Central nervous system, Ceramic, Chalcogen, Charles Darwin, Chemical affinity, Chemical bond, Chemical compound, Chemical element, Chemical formula, Chemical oxygen generator, Chemical polarity, Chemical reaction, Chloride, Chloroplast, Chronic obstructive pulmonary disease, Citric acid, Classical element, Cluster chemistry, CNO cycle, Cofactor (biochemistry), Combustion, Compounds of oxygen, Convulsion, Corrosion, Corrosion in space, Corundum, Covalent bond, CRC Press, Crust (geology), Cryogenics, Cyanobacteria, Decomposition, Decompression (diving), Decompression sickness, Degenerate energy levels, Detergent, Detonation, Diatomic molecule, Diethyl ether, Diffuse sky radiation, Diffusion, Dimethyl sulfoxide, Dimethylformamide, Dioxygen difluoride, Dioxygen in biological reactions, Dioxygenyl, Dioxygenyl hexafluoroplatinate, Dipole, Disease, Distillation, Diving chamber, Double bond, Earth, Earth observation satellite, Electrolysis of water, Electromagnetic spectrum, Electron configuration, Electronegativity, Enzyme, Epoxide, Erasmus Darwin, Ester, Ethanol, Ether, Ethyl acetate, Ethylene, Ethylene glycol, Ethylene oxide, Eukaryote, Euphoria, Eutrophication, Evaporation, Evolutionary history of life, Exchange interaction, Exhaust system, Exoskeleton, Exothermic process, Exothermic reaction, Experiments and Observations on Different Kinds of Air, Explosion, Extinction, Fat, Fire, Fire (classical element), Fixed-wing aircraft, Fluorescence, Fluorine, Formaldehyde, Formic acid, Foundations of Chemistry, Fractional distillation, French Academy of Sciences, Fuel, Furan, Gas, Gas gangrene, Gasoline, Genesis (spacecraft), Geological history of oxygen, Geology of solar terrestrial planets, Georg Ernst Stahl, George H. Goble, Glucose, Glutaraldehyde, Glycerol, Granite, Great Oxygenation Event, Green algae, Ground state, Group (periodic table), Half-life, Heart failure, Heat exchanger, Helium, Helium-4, Hematite, Heme, Hemerythrin, Hemocyanin, Hemoglobin, Hexagonal crystal family, Human spaceflight, Humphry Davy, Hydrogen, Hydrogen bond, Hydrogen peroxide, Hyperbaric medicine, Hyperbaric treatment schedules, Hyperoxia, Hypersensitive response, Hypofluorous acid, Hypoxia (environmental), Hypoxia (medical), Ice core, Immune system, Inorganic compound, International Union of Pure and Applied Chemistry, Iron, Iron ore, Iron(II) oxide, Iron(III) oxide, Isopropyl alcohol, Isotope, Isotopes of nitrogen, Isotopes of oxygen, Jagiellonian University, James Dewar, Johann Joachim Becher, John Dalton, John Mayow, Joseph Louis Gay-Lussac, Joseph Priestley, Joule per mole, Karol Olszewski, Kelvin, Ketone, Las Vegas Valley, Leonardo da Vinci, Life support system, Ligand, Limestone, Limiting oxygen concentration, Liquid oxygen, List of underwater divers, Lithosphere, Litre, Lobster, Louis Paul Cailletet, Low Earth orbit, Magnesium, Magnet, Magnetic moment, Manganese, Mars, Mechanical ventilation, Medicine, Mercury(II) oxide, Mesosphere, Metal, Metastability, Meteorite, Methanol, Mikhail Eremets, Mikhail Lomonosov, Milky Way, Millimeter of mercury, Mitochondrion, Molecular orbital, Mollusca, Moon, Myoglobin, Nanometre, NASA, Nasal cannula, Natural abundance, Nebular hypothesis, Neon, Neon-burning process, Nevada, NFPA 704, Nitrate, Nitrogen, Non-stoichiometric compound, Nonmetal, Nucleic acid, Nucleosynthesis, Obligate anaerobe, Ocean deoxygenation, Ole Borch, Organic acid anhydride, Organic chemistry, Organic compound, Organism, Outgassing, Oxidation state, Oxidative phosphorylation, Oxide, Oxidizing agent, Oxy-fuel welding and cutting, Oxyacid, Oxygen bar, Oxygen cycle, Oxygen difluoride, Oxygen evolution, Oxygen isotope ratio cycle, Oxygen mask, Oxygen plant, Oxygen sensor, Oxygen storage, Oxygen tank, Oxygen tent, Oxygen therapy, Oxygen toxicity, Oxygen-16, Oxygen-17, Oxygen-18, Oxygen-evolving complex, Ozone, Ozone layer, Ozonide, Paleoclimatology, Paleoproterozoic, Paramagnetism, Partial pressure, Pascal (unit), Passivation (chemistry), Peracetic acid, Periodic table, Periodic Videos, Peroxide, Petrochemical, Phenol, Philo of Byzantium, Philosopher, Phlogiston theory, Phosphate, Photodissociation, Photon, Photophosphorylation, Photosynthesis, Picometre, Pierre Bayen, Placebo, Plastic, Platinum hexafluoride, Pneumonia, Polish Scientific Publishers PWN, Polyester, Positron emission, Potassium nitrate, Pressure swing adsorption, Preterm birth, Protein, Proton, Protoplanetary disk, Pulmonary artery, Pulmonary fibrosis, Pulmonary gas pressures, Pyrotechnics, Quantum mechanics, Quartz, Radioactive decay, Radionuclide, Raoul Pictet, Rayleigh scattering, Reactive oxygen species, Rebreather, Red blood cell, Redox, Reflectance, Remote sensing, Residue (chemistry), Respiration (physiology), Respiratory system, Robert Boyle, Robert H. Goddard, Robert Hooke, Rock (geology), Rocket engine, Rocket propellant, Royal Society of Chemistry, Rust, Schumann–Runge bands, Scuba diving, Seawater, Sendivogius, Signal-to-noise ratio, Silicate, Silicate minerals, Silicon, Silicon dioxide, Singlet oxygen, Skeleton, Smelting, Smog, Sodium chlorate, Solar System, Solar wind, Solid oxygen, Solubility, Solvent, Space suit, Spider, Spin (physics), Sport, Standard conditions for temperature and pressure, Star, Steel, Submarine, Sulfur, Sulfur dioxide, Sun, Superconductivity, Superoxide, Surface-supplied diving, Tetrahydrofuran, Tetraoxygen, Textile, The Botanic Garden, The New York Times, Thylakoid, Tin, Titanium, Transition metal, Transition metal dioxygen complex, Triple-alpha process, Triplet oxygen, Triplet state, Troposphere, Ultraviolet, Underwater diving, Uppsala, Vacuum swing adsorption, Van der Waals force, Vein, Venus, Vertebrate, Water, Water pollution, Water treatment, Wave–particle duality, Wüstite, Welding, Wiltshire, Wood, Zeolite, Zirconium dioxide, Zygmunt Florenty Wróblewski, 1,4-Dioxane. 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According to quantum mechanics, atoms and molecules can only hold certain defined quantities of energy, or exist in specific states.
The abundance of the chemical elements is a measure of the occurrence of the chemical elements relative to all other elements in a given environment.
Acetamide (systematic name: ethanamide) is an organic compound with the formula CH3CONH2.
Acetic acid, systematically named ethanoic acid, is a colourless liquid organic compound with the chemical formula CH3COOH (also written as CH3CO2H or C2H4O2).
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH3CO)2O.
Acetone (systematically named propanone) is the organic compound with the formula (CH3)2CO.
Acetylene (systematic name: ethyne) is the chemical compound with the formula C2H2.
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).
Adenosine triphosphate (ATP) is a complex organic chemical that participates in many processes.
An adhesive, also known as glue, cement, mucilage, or paste, is any substance applied to one surface, or both surfaces, of two separate items that binds them together and resists their separation.
An aerobic organism or aerobe is an organism that can survive and grow in an oxygenated environment.
Air pollution occurs when harmful or excessive quantities of substances including gases, particulates, and biological molecules are introduced into Earth's atmosphere.
An aircraft is a machine that is able to fly by gaining support from the air.
Airglow (also called nightglow) is a faint emission of light by a planetary atmosphere.
Alchemy is a philosophical and protoscientific tradition practiced throughout Europe, Africa, Brazil and Asia.
In chemistry, an alcohol is any organic compound in which the hydroxyl functional group (–OH) is bound to a carbon.
An aldehyde or alkanal is an organic compound containing a functional group with the structure −CHO, consisting of a carbonyl center (a carbon double-bonded to oxygen) with the carbon atom also bonded to hydrogen and to an R group, which is any generic alkyl or side chain.
Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 17696 May 1859) was a Prussian polymath, geographer, naturalist, explorer, and influential proponent of Romantic philosophy and science.
There are several known allotropes of oxygen.
Allotropy or allotropism is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of these elements.
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.
The ambient pressure on an object is the pressure of the surrounding medium, such as a gas or liquid, in contact with the object.
Amedeo Carlo Avogadro, Count of Quaregna and Cerreto (9 August 17769 July 1856), was an Italian scientist, most noted for his contribution to molecular theory now known as Avogadro's law, which states that equal volumes of gases under the same conditions of temperature and pressure will contain equal numbers of molecules.
American football, referred to as football in the United States and Canada and also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end.
An amide (or or), also known as an acid amide, is a compound with the functional group RnE(O)xNR′2 (R and R′ refer to H or organic groups).
An anaerobic organism or anaerobe is any organism that does not require oxygen for growth.
Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 13th–9th centuries BC to the end of antiquity (AD 600).
The Ancient Greek language includes the forms of Greek used in ancient Greece and the ancient world from around the 9th century BC to the 6th century AD.
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).
Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia.
In chemical bonding theory, an antibonding orbital is a type of molecular orbital (MO) that weakens the bond between two atoms and helps to raise the energy of the molecule relative to the separated atoms.
An antifreeze is an additive which lowers the freezing point of a water-based liquid and increases its boiling point.
Antimony is a chemical element with symbol Sb (from stibium) and atomic number 51.
Antoine-Laurent de Lavoisier (also Antoine Lavoisier after the French Revolution;; 26 August 17438 May 1794) CNRS (Centre National de la Recherche Scientifique) was a French nobleman and chemist who was central to the 18th-century chemical revolution and who had a large influence on both the history of chemistry and the history of biology.
The Apollo spacecraft was composed of three parts designed to accomplish the American Apollo program's goal of landing astronauts on the Moon by the end of the 1960s and returning them safely to Earth.
Apollo 1, initially designated AS-204, was the first manned mission of the United States Apollo program, the program to land the first men on the Moon.
Archaea (or or) constitute a domain of single-celled microorganisms.
An artery (plural arteries) is a blood vessel that takes blood away from the heart to all parts of the body (tissues, lungs, etc).
An arthropod (from Greek ἄρθρον arthron, "joint" and πούς pous, "foot") is an invertebrate animal having an exoskeleton (external skeleton), a segmented body, and paired jointed appendages.
Asphalt, also known as bitumen, is a sticky, black, and highly viscous liquid or semi-solid form of petroleum.
ASTM International is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services.
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 atmospheric diving suit (ADS) is a small one-person articulated anthropomorphic submersible which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere.
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.
In quantum mechanics, an atomic orbital is a mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom.
Auburn is a town in Worcester County, Massachusetts, United States.
The aufbau principle states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
An aurora (plural: auroras or aurorae), sometimes referred to as polar lights, northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions (around the Arctic and Antarctic).
Autoxidation is any oxidation that occurs in open air or in presence of oxygen (and sometimes UV radiation) and forms peroxides and hydroperoxides.
Avogadro's law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) is an experimental gas law relating the volume of a gas to the amount of substance of gas present.
Bacteria (common noun bacteria, singular bacterium) is a type of biological cell.
Banded iron formations (also known as banded ironstone formations or BIFs) are distinctive units of sedimentary rock that are almost always of Precambrian age.
Barbecue or barbeque (informally BBQ or barbie) is a cooking method, a style of food, and a name for a meal or gathering at which this style of food is cooked and served.
Bauxite is a sedimentary rock with a relatively high aluminium content.
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.
Biochemical Oxygen Demand (BOD, also called Biological Oxygen Demand) is the amount of dissolved oxygen needed (i.e. demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period.
In geography and Earth science, a biogeochemical cycle or substance turnover or cycling of substances is a pathway by which a chemical substance moves through biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) compartments of Earth.
A biomolecule or biological molecule is a loosely used term for molecules and ions that are present in organisms, essential to some typically biological process such as cell division, morphogenesis, or development.
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.
The Bohr effect is a physiological phenomenon first described in 1904 by the Danish physiologist Christian Bohr: hemoglobin's oxygen binding affinity (see Oxygen–haemoglobin dissociation curve) is inversely related both to acidity and to the concentration of carbon dioxide.
Bond order is the number of chemical bonds between a pair of atoms.
Breathing (or respiration, or ventilation) is the process of moving air into and out of the lungs to facilitate gas exchange with the internal environment, mostly by bringing in oxygen and flushing out carbon dioxide.
A breathing gas is a mixture of gaseous chemical elements and compounds used for respiration.
Calcium is a chemical element with symbol Ca and atomic number 20.
Calcium carbonate is a chemical compound with the formula CaCO3.
California is a state in the Pacific Region of the United States.
Calx is a substance formed from an ore or mineral that has been heated.
The Cambrian Period was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon.
A carbohydrate is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water); in other words, with the empirical formula (where m may be different from n).
Carbon (from carbo "coal") is a chemical element with symbol C and atomic number 6.
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.
Carbon dioxide (chemical formula) is a colorless gas with a density about 60% higher than that of dry air.
Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.
Carbon monoxide poisoning typically occurs from breathing in too much carbon monoxide (CO).
The Carboniferous is a geologic period and system that spans 60 million years from the end of the Devonian Period million years ago (Mya), to the beginning of the Permian Period, Mya.
A carboxylic acid is an organic compound that contains a carboxyl group (C(.
Carl Paul Gottfried Linde (11 June 1842 – 16 November 1934) was a German scientist, engineer, and businessman.
Carl Wilhelm Scheele (9 December 1742 – 21 May 1786) was a Swedish Pomeranian and German pharmaceutical chemist.
Carotenoids, also called tetraterpenoids, are organic pigments that are produced by plants and algae, as well as several bacteria and fungi.
In chemical engineering, a cascade is a plant consisting of several similar stages with each processing the output from the previous stage.
Cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.
The Celsius scale, previously known as the centigrade scale, is a temperature scale used by the International System of Units (SI).
The central nervous system (CNS) is the part of the nervous system consisting of the brain and spinal cord.
A ceramic is a non-metallic solid material comprising an inorganic compound of metal, non-metal or metalloid atoms primarily held in ionic and covalent bonds.
The chalcogens are the chemical elements in group 16 of the periodic table.
Charles Robert Darwin, (12 February 1809 – 19 April 1882) was an English naturalist, geologist and biologist, best known for his contributions to the science of evolution.
In chemical physics and physical chemistry, chemical affinity is the electronic property by which dissimilar chemical species are capable of forming chemical compounds.
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds.
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).
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.
A chemical oxygen generator is a device that releases oxygen via a chemical reaction.
In chemistry, polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole or multipole moment.
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.
The chloride ion is the anion (negatively charged ion) Cl−.
Chloroplasts are organelles, specialized compartments, in plant and algal cells.
Chronic obstructive pulmonary disease (COPD) is a type of obstructive lung disease characterized by long-term breathing problems and poor airflow.
Citric acid is a weak organic acid that has the chemical formula.
Classical elements typically refer to the concepts in ancient Greece of earth, water, air, fire, and aether, which were proposed to explain the nature and complexity of all matter in terms of simpler substances.
In chemistry, a cluster is an ensemble of bound atoms or molecules that is intermediate in size between a molecule and a bulk solid.
The CNO cycle (for carbon–nitrogen–oxygen) is one of the two known sets of fusion reactions by which stars convert hydrogen to helium, the other being the proton–proton chain reaction.
A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's activity.
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke.
The oxidation state of oxygen is −2 in almost all known compounds of oxygen.
A convulsion is a medical condition where body muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body.
Corrosion is a natural process, which converts a refined metal to a more chemically-stable form, such as its oxide, hydroxide, or sulfide.
Corrosion in space is the corrosion of materials occurring in outer space.
Corundum is a crystalline form of aluminium oxide typically containing traces of iron, titanium, vanadium and chromium.
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms.
The CRC Press, LLC is a publishing group based in the United States that specializes in producing technical books.
In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite.
In physics, cryogenics is the production and behaviour of materials at very low temperatures.
Cyanobacteria, also known as Cyanophyta, are a phylum of bacteria that obtain their energy through photosynthesis, and are the only photosynthetic prokaryotes able to produce oxygen.
Decomposition is the process by which organic substances are broken down into simpler organic matter.
The decompression of a diver is the reduction in ambient pressure experienced during ascent from depth.
Decompression sickness (DCS; also known as divers' disease, the bends, aerobullosis, or caisson disease) describes a condition arising from dissolved gases coming out of solution into bubbles inside the body on depressurisation.
In quantum mechanics, an energy level is degenerate if it corresponds to two or more different measurable states of a quantum system.
A detergent is a surfactant or a mixture of surfactants with cleaning properties in dilute solutions.
Detonation is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it.
Diatomic molecules are molecules composed of only two atoms, of the same or different chemical elements.
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula, sometimes abbreviated as (see Pseudoelement symbols).
Diffuse sky radiation is solar radiation reaching the Earth's surface after having been scattered from the direct solar beam by molecules or particulates in the atmosphere.
Diffusion is the net movement of molecules or atoms from a region of high concentration (or high chemical potential) to a region of low concentration (or low chemical potential) as a result of random motion of the molecules or atoms.
Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula (CH3)2SO.
Dimethylformamide is an organic compound with the formula (CH3)2NC(O)H.
Dioxygen difluoride is a compound of fluorine and oxygen with the molecular formula.
Dioxygen plays an important role in the energy metabolism of living organisms.
The dioxygenyl ion,, is a rarely-encountered oxycation in which both oxygen atoms have a formal oxidation state of +. It is formally derived from oxygen by the removal of an electron: The energy change for this process is called the ionization energy of the oxygen molecule.
Dioxygenyl hexafluoroplatinate is a compound with formula O2PtF6.
In electromagnetism, there are two kinds of dipoles.
A disease is any condition which results in the disorder of a structure or function in an organism that is not due to any external injury.
Distillation is the process of separating the components or substances from a liquid mixture by selective boiling and condensation.
A diving chamber is a vessel for human occupation, which may have an entrance that can be sealed to hold an internal pressure significantly higher than ambient pressure, a pressurised gas system to control the internal pressure, and a supply of breathing gas for the occupants.
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Earth observation satellites are satellites specifically designed for Earth observation from orbit, similar to spy satellites but intended for non-military uses such as environmental monitoring, meteorology, map making etc.
Electrolysis of water is the decomposition of water into oxygen and hydrogen gas due to an electric current passed through the water.
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies.
In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals.
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.
Enzymes are macromolecular biological catalysts.
An epoxide is a cyclic ether with a three-atom ring.
Erasmus Darwin (12 December 173118 April 1802) was an English physician.
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.
Ethanol, also called alcohol, ethyl alcohol, grain alcohol, and drinking alcohol, is a chemical compound, a simple alcohol with the chemical formula.
Ethers are a class of organic compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups.
Ethyl acetate (systematically ethyl ethanoate, commonly abbreviated EtOAc or EA) is the organic compound with the formula, simplified to.
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or H2C.
Ethylene glycol (IUPAC name: ethane-1,2-diol) is an organic compound with the formula (CH2OH)2.
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..
Eukaryotes are organisms whose cells have a nucleus enclosed within membranes, unlike Prokaryotes (Bacteria and other Archaea).
Euphoria is an affective state in which a person experiences pleasure or excitement and intense feelings of well-being and happiness.
Eutrophication (from Greek eutrophos, "well-nourished"), or hypertrophication, is when a body of water becomes overly enriched with minerals and nutrients that induce excessive growth of plants and algae.
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gaseous phase before reaching its boiling point.
The evolutionary history of life on Earth traces the processes by which both living organisms and fossil organisms evolved since life emerged on the planet, until the present.
In physics, the exchange interaction (with an exchange energy, and exchange term) is a quantum mechanical effect that only occurs between identical particles.
An exhaust system is usually piping used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove.
An exoskeleton (from Greek έξω, éxō "outer" and σκελετός, skeletós "skeleton") is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton (endoskeleton) of, for example, a human.
In thermodynamics, the term exothermic process (exo-: "outside") describes a process or reaction that releases energy from the system to its surroundings, usually in the form of heat, but also in a form of light (e.g. a spark, flame, or flash), electricity (e.g. a battery), or sound (e.g. explosion heard when burning hydrogen).
An exothermic reaction is a chemical reaction that releases energy by light or heat.
Experiments and Observations on Different Kinds of Air (1774–86) is a six-volume work published by 18th-century British polymath Joseph Priestley which reports a series of his experiments on "airs" or gases, most notably his discovery of oxygen gas (which he called "dephlogisticated air").
An explosion is a rapid increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases.
In biology, extinction is the termination of an organism or of a group of organisms (taxon), normally a species.
Fat is one of the three main macronutrients, along with carbohydrate and protein.
Fire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products.
Fire has been an important part of all cultures and religions from pre-history to modern day and was vital to the development of civilization.
A fixed-wing aircraft is an aircraft, such as an airplane or aeroplane (note the two different spellings), which is capable of flight using wings that generate lift caused by the vehicle's forward airspeed and the shape of the wings.
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
Fluorine is a chemical element with symbol F and atomic number 9.
Formic acid, systematically named methanoic acid, is the simplest carboxylic acid.
Foundations of Chemistry is a triannual peer-reviewed academic journal covering conceptual and fundamental issues related to chemistry, including philosophy and history of chemistry, and chemistry education.
Fractional distillation is the separation of a mixture into its component parts, or fractions.
The French Academy of Sciences (French: Académie des sciences) is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research.
A fuel is any material that can be made to react with other substances so that it releases energy as heat energy or to be used for work.
Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen.
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
Gas gangrene (also known as clostridial myonecrosis and myonecrosis) is a bacterial infection that produces gas in tissues in gangrene.
Gasoline (American English), or petrol (British English), is a transparent, petroleum-derived liquid that is used primarily as a fuel in spark-ignited internal combustion engines.
Genesis was a NASA sample-return probe that collected a sample of solar wind particles and returned them to Earth for analysis.
Before photosynthesis evolved, Earth's atmosphere had no free oxygen (O2).
The geology of solar terrestrial planets mainly deals with the geological aspects of the four terrestrial planets of the Solar System, Mercury, Venus, Earth, and Mars, and one terrestrial dwarf planet, Ceres.
Georg Ernst Stahl (22 October 1659 – 24 May 1734) was a German chemist, physician and philosopher.
George H. Goble is a staff member at the Purdue University Engineering Computer Network and a 1996 Ig Nobel Prize winner.
Glucose is a simple sugar with the molecular formula C6H12O6.
Glutaraldehyde, sold under the brandname Cidex and Glutaral among others, is a disinfectant and medication.
Glycerol (also called glycerine or glycerin; see spelling differences) is a simple polyol compound.
Granite is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture.
The Great Oxygenation Event, the beginning of which is commonly known in scientific media as the Great Oxidation Event (GOE, also called the Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust, Oxygen Revolution, or Great Oxidation) was the biologically induced appearance of dioxygen (O2) in Earth's atmosphere.
The green algae (singular: green alga) are a large, informal grouping of algae consisting of the Chlorophyta and Charophyta/Streptophyta, which are now placed in separate divisions, as well as the more basal Mesostigmatophyceae, Chlorokybophyceae and Spirotaenia.
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.
In chemistry, a group (also known as a family) is a column of elements in the periodic table of the chemical elements.
Half-life (symbol t1⁄2) is the time required for a quantity to reduce to half its initial value.
Heart failure (HF), often referred to as congestive heart failure (CHF), is when the heart is unable to pump sufficiently to maintain blood flow to meet the body's needs.
A heat exchanger is a device used to transfer heat between two or more fluids.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
Helium-4 is a non-radioactive isotope of the element helium.
Hematite, also spelled as haematite, is the mineral form of iron(III) oxide (Fe2O3), one of several iron oxides.
Heme or haem is a coordination complex "consisting of an iron ion coordinated to a porphyrin acting as a tetradentate ligand, and to one or two axial ligands." The definition is loose, and many depictions omit the axial ligands.
Hemerythrin (also spelled haemerythrin; blood, red) is an oligomeric protein responsible for oxygen (O2) transport in the marine invertebrate phyla of sipunculids, priapulids, brachiopods, and in a single annelid worm genus, Magelona.
Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals.
Hemoglobin (American) or haemoglobin (British); abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein in the red blood cells of all vertebrates (with the exception of the fish family Channichthyidae) as well as the tissues of some invertebrates.
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).
Human spaceflight (also referred to as crewed spaceflight or manned spaceflight) is space travel with a crew or passengers aboard the spacecraft.
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.
Hydrogen is a chemical element with symbol H and atomic number 1.
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 peroxide is a chemical compound with the formula.
Hyperbaric medicine is medical treatment in which an ambient pressure greater than sea level atmospheric pressure is a necessary component.
Hyperbaric treatment schedules or hyperbaric treatment tables, are planned sequences of events in chronological order for hyperbaric pressure exposures specifying the pressure profile over time and the breathing gas to be used during specified periods, for medical treatment.
Hyperoxia occurs when cells, tissues and organs are exposed to an excess supply of oxygen (O2) or higher than normal partial pressure of oxygen.
The hypersensitive response (HR) is a mechanism, used by plants, to prevent the spread of infection by microbial pathogens.
Hypofluorous acid, HOF, is the only known oxoacid of fluorine and the only known oxoacid which the main atom gains electrons from oxygen to create a negative oxidation state.
Hypoxia refers to low oxygen conditions.
Hypoxia is a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level.
An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier.
The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease.
An inorganic compound is typically a chemical compound that lacks C-H bonds, that is, a compound that is not an organic compound, but the distinction is not defined or even of particular interest.
The International Union of Pure and Applied Chemistry (IUPAC) is an international federation of National Adhering Organizations that represents chemists in individual countries.
Iron is a chemical element with symbol Fe (from ferrum) and atomic number 26.
Iron ores are rocks and minerals from which metallic iron can be economically extracted.
Iron(II) oxide or ferrous oxide is the inorganic compound with the formula FeO.
Iron(III) oxide or ferric oxide is the inorganic compound with the formula Fe2O3.
Isopropyl alcohol (IUPAC name propan-2-ol; commonly called isopropanol) is a compound with the chemical formula C3H8O.
Isotopes are variants of a particular chemical element which differ in neutron number.
Natural nitrogen (7N) consists of two stable isotopes, nitrogen-14, which makes up the vast majority of naturally occurring nitrogen, and nitrogen-15, which is less common.
There are three known stable isotopes of oxygen (8O): 16O, 17O, and 18O.
The Jagiellonian University (Polish: Uniwersytet Jagielloński; Latin: Universitas Iagellonica Cracoviensis, also known as the University of Kraków) is a research university in Kraków, Poland.
Sir James Dewar FRS FRSE (20 September 1842 – 27 March 1923) was a Scottish chemist and physicist.
Johann Joachim Becher (6 May 1635 – October 1682) was a German physician, alchemist, precursor of chemistry, scholar and adventurer, best known for his development of the phlogiston theory of combustion, and his advancement of Austrian cameralism.
John Dalton FRS (6 September 1766 – 27 July 1844) was an English chemist, physicist, and meteorologist.
John Mayow FRS (1641–1679) was a chemist, physician, and physiologist who is remembered today for conducting early research into respiration and the nature of air.
Joseph Louis Gay-Lussac (also Louis Joseph Gay-Lussac; 6 December 1778 – 9 May 1850) was a French chemist and physicist.
Joseph Priestley FRS (– 6 February 1804) was an 18th-century English Separatist theologian, natural philosopher, chemist, innovative grammarian, multi-subject educator, and liberal political theorist who published over 150 works.
The joule per mole (symbol: J·mole−1 or J/mol) is an SI derived unit of energy per amount of material.
Karol Stanisław Olszewski (29 January 1846 – 24 March 1915) was a Polish chemist, mathematician and physicist.
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.
In chemistry, a ketone (alkanone) is an organic compound with the structure RC(.
The Las Vegas Valley is a major metropolitan area in the southern part of the U.S. state of Nevada.
Leonardo di ser Piero da Vinci (15 April 14522 May 1519), more commonly Leonardo da Vinci or simply Leonardo, was an Italian polymath of the Renaissance, whose areas of interest included invention, painting, sculpting, architecture, science, music, mathematics, engineering, literature, anatomy, geology, astronomy, botany, writing, history, and cartography.
In human spaceflight, a life support system is a group of devices that allow a human being to survive in space.
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex.
Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs.
The limiting oxygen concentration, (LOC), also known as the minimum oxygen concentration, (MOC), is defined as the limiting concentration of oxygen below which combustion is not possible, independent of the concentration of fuel.
Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is one of the physical forms of elemental oxygen.
This is a list of underwater divers whose exploits have made them notable.
A lithosphere (λίθος for "rocky", and σφαίρα for "sphere") is the rigid, outermost shell of a terrestrial-type planet, or natural satellite, that is defined by its rigid mechanical properties.
The litre (SI spelling) or liter (American spelling) (symbols L or l, sometimes abbreviated ltr) is an SI accepted metric system unit of volume equal to 1 cubic decimetre (dm3), 1,000 cubic centimetres (cm3) or 1/1,000 cubic metre. A cubic decimetre (or litre) occupies a volume of 10 cm×10 cm×10 cm (see figure) and is thus equal to one-thousandth of a cubic metre. The original French metric system used the litre as a base unit. The word litre is derived from an older French unit, the litron, whose name came from Greek — where it was a unit of weight, not volume — via Latin, and which equalled approximately 0.831 litres. The litre was also used in several subsequent versions of the metric system and is accepted for use with the SI,, p. 124. ("Days" and "hours" are examples of other non-SI units that SI accepts.) although not an SI unit — the SI unit of volume is the cubic metre (m3). The spelling used by the International Bureau of Weights and Measures is "litre", a spelling which is shared by almost all English-speaking countries. The spelling "liter" is predominantly used in American English. One litre of liquid water has a mass of almost exactly one kilogram, because the kilogram was originally defined in 1795 as the mass of one cubic decimetre of water at the temperature of melting ice. Subsequent redefinitions of the metre and kilogram mean that this relationship is no longer exact.
Lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans.
Louis-Paul Cailletet (21 September 1832 – 5 January 1913) was a French physicist and inventor.
A low Earth orbit (LEO) is an orbit around Earth with an altitude of or less, and with an orbital period of between about 84 and 127 minutes.
Magnesium is a chemical element with symbol Mg and atomic number 12.
A magnet is a material or object that produces a magnetic field.
The magnetic moment is a quantity that represents the magnetic strength and orientation of a magnet or other object that produces a magnetic field.
Manganese is a chemical element with symbol Mn and atomic number 25.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
Mechanical ventilation is the medical term for artificial ventilation where mechanical means is used to assist or replace spontaneous breathing. This may involve a machine called a ventilator or the breathing may be assisted by an anesthesiologist, certified registered nurse anesthetist, physician, physician assistant, respiratory therapist, paramedic, EMT, or other suitable person compressing a bag or set of bellows. Mechanical ventilation is termed "invasive" if it involves any instrument penetrating the trachea through the mouth, such as an endotracheal tube or the skin, such as a tracheostomy tube. There are two main types: positive pressure ventilation, where air (or another gas mix) is pushed into the trachea, and negative pressure ventilation, where air is, in essence, sucked into the lungs. There are many modes of mechanical ventilation, and their nomenclature has been revised over the decades as the technology has continually developed.
Medicine is the science and practice of the diagnosis, treatment, and prevention of disease.
Mercury(II) oxide, also called mercuric oxide or simply mercury oxide, has a formula of HgO.
The mesosphere (from Greek mesos "middle" and sphaira "sphere") is the layer of the Earth's atmosphere that is directly above the stratosphere and directly below the thermosphere.
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.
In physics, metastability is a stable state of a dynamical system other than the system's state of least energy.
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon.
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).
Mikhail Ivanovich Eremets (born 3 January 1949) is an experimentalist in high pressure physics, chemistry, and materials science.
Mikhail Vasilyevich Lomonosov (ləmɐˈnosəf|a.
The Milky Way is the galaxy that contains our Solar System.
A millimeter of mercury is a manometric unit of pressure, formerly defined as the extra pressure generated by a column of mercury one millimetre high and now defined as precisely pascals.
The mitochondrion (plural mitochondria) is a double-membrane-bound organelle found in most eukaryotic organisms.
In chemistry, a molecular orbital (MO) is a mathematical function describing the wave-like behavior of an electron in a molecule.
Mollusca is a large phylum of invertebrate animals whose members are known as molluscs or mollusksThe formerly dominant spelling mollusk is still used in the U.S. — see the reasons given in Gary Rosenberg's.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
Myoglobin (symbol Mb or MB) is an iron- and oxygen-binding protein found in the muscle tissue of vertebrates in general and in almost all mammals.
The nanometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American spelling) is a unit of length in the metric system, equal to one billionth (short scale) of a metre (m).
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
The nasal cannula (NC) is a device used to deliver supplemental oxygen or increased airflow to a patient or person in need of respiratory help.
In physics, natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet.
The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems).
Neon is a chemical element with symbol Ne and atomic number 10.
The neon-burning process (nuclear decay) is a set of nuclear fusion reactions that take place in massive stars (at least 8 Solar masses).
Nevada (see pronunciations) is a state in the Western, Mountain West, and Southwestern regions of the United States of America.
"NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response" is a standard maintained by the U.S.-based National Fire Protection Association.
Nitrate is a polyatomic ion with the molecular formula and a molecular mass of 62.0049 u.
Nitrogen is a chemical element with symbol N and atomic number 7.
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.
Apart from hydrogen, nonmetals are located in the p-block. Helium, as an s-block element, would normally be placed next to hydrogen and above beryllium. However, since it is a noble gas, it is instead placed above neon (in the p-block). In chemistry, a nonmetal (or non-metal) is a chemical element that mostly lacks metallic attributes.
Nucleic acids are biopolymers, or small biomolecules, essential to all known forms of life.
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons.
Obligate anaerobes are microorganisms killed by normal atmospheric concentrations of oxygen (20.95% O2).
Ocean deoxygenation is the expansion of oxygen minimum zones in the world's oceans as a consequence of anthropogenic emissions of carbon dioxide.
Ole Borch (Jutland, 1626 – 1690) (latinized to Olaus Borrichius or Olaus Borrichus) was a Danish scientist, physician, grammarian, and poet, most famous today for being the teacher at the Vor Frue Skole in Copenhagen of Nicholas Steno.
An organic acid anhydride is an acid anhydride that is an organic compound.
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.
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.
Outgassing (sometimes called offgassing, particularly when in reference to indoor air quality) is the release of a gas that was dissolved, trapped, frozen or absorbed in some material.
The oxidation state, sometimes referred to as oxidation number, describes degree of oxidation (loss of electrons) of an atom in a chemical compound.
Oxidative phosphorylation (or OXPHOS in short) (UK, US) is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing energy which is used to produce adenosine triphosphate (ATP).
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.
Principle of the burn cutting Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the U.S.) and oxy-fuel cutting are processes that use fuel gases and oxygen to weld and cut metals, respectively.
An oxyacid, or oxoacid, is an acid that contains oxygen.
An oxygen bar is an establishment, or part of one, that sells oxygen for recreational use.
The oxygen cycle is the biogeochemical cycle of oxygen within its four main reservoirs: the atmosphere (air), the total content of biological matter within the biosphere (the global sum of all ecosystems), the hydrosphere (the combined mass of water found on, under, and over the surface of planet Earth), and the lithosphere/Earth's crust.
Oxygen difluoride is the chemical compound with the formula OF2.
Oxygen evolution is the process of generating molecular oxygen through chemical reaction.
Oxygen isotope ratio cycles are cyclical variations in the ratio of the abundance of oxygen with an atomic mass of 18 to the abundance of oxygen with an atomic mass of 16 present in some substances, such as polar ice or calcite in ocean core samples, measured with the isotope fractionation.
An oxygen mask provides a method to transfer breathing oxygen gas from a storage tank to the lungs.
Oxygen plants are industrial systems designed to generate oxygen.
An oxygen sensor (or lambda sensor) is an electronic device that measures the proportion of oxygen (O2) in the gas or liquid being analysed.
Methods of oxygen storage for subsequent use span many approaches, including high pressures in oxygen tanks, cryogenics, oxygen-rich compounds and reaction mixtures, and chemical compounds that reversibly release oxygen upon heating or pressure change.
An oxygen tank is an oxygen storage vessel, which is either held under pressure in gas cylinders, or as liquid oxygen in a cryogenic storage tank.
An oxygen tent consists of a canopy placed over the head and shoulders, or over the entire body of a patient to provide oxygen at a higher level than normal.
Oxygen therapy, also known as supplemental oxygen, is the use of oxygen as a medical treatment.
Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen at increased partial pressures.
Oxygen-16 (16O) is a stable isotope of oxygen, having 8 neutrons and 8 protons in its nucleus.
Oxygen-17 is a low-abundant, natural, stable isotope of oxygen (0.0373% in seawater; approximately twice as abundant as deuterium).
Oxygen-18 is a natural, stable isotope of oxygen and one of the environmental isotopes.
The oxygen-evolving complex (OEC), also known as the water-splitting complex, is a water-oxidizing enzyme involved in the photo-oxidation of water during the light reactions of photosynthesis.
Ozone, or trioxygen, is an inorganic molecule with the chemical formula.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation.
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.
Paleoclimatology (in British spelling, palaeoclimatology) is the study of changes in climate taken on the scale of the entire history of Earth.
Paleoproterozoic Era, spanning the time period from (2.5–1.6 Ga), is the first of the three sub-divisions (eras) of the Proterozoic Eon.
Paramagnetism is a form of magnetism whereby certain materials are weakly attracted by an externally applied magnetic field, and form internal, induced magnetic fields in the direction of the applied magnetic field.
In a mixture of gases, each gas has a partial pressure which is the hypothetical pressure of that gas if it alone occupied the entire volume of the original mixture at the same temperature.
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
Passivation, in physical chemistry and engineering, refers to a material becoming "passive," that is, less affected or corroded by the environment of future use.
Peracetic acid (also known as peroxyacetic acid, or PAA), is an organic compound with the formula CH3CO3H.
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.
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.
Petrochemicals (also known as petroleum distillates) are chemical products derived from petroleum.
Phenol, also known as phenolic acid, is an aromatic organic compound with the molecular formula C6H5OH.
Philo of Byzantium (Φίλων ὁ Βυζάντιος, Philōn ho Byzantios, ca. 280 BC – ca. 220 BC), also known as Philo Mechanicus, was a Greek engineer, physicist and writer on mechanics, who lived during the latter half of the 3rd century BC.
A philosopher is someone who practices philosophy, which involves rational inquiry into areas that are outside either theology or science.
The phlogiston theory is a superseded scientific theory that postulated that a fire-like element called phlogiston is contained within combustible bodies and released during combustion.
A phosphate is chemical derivative of phosphoric acid.
Photodissociation, photolysis, or photodecomposition is a chemical reaction in which a chemical compound is broken down by photons.
The photon is a type of elementary particle, the quantum of the electromagnetic field including electromagnetic radiation such as light, and the force carrier for the electromagnetic force (even when static via virtual particles).
In the process of photosynthesis, the phosphorylation of ADP to form ATP using the energy of sunlight is called photophosphorylation.
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities (energy transformation).
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.
Pierre Bayen (1725-1798) was a French chemist.
A placebo is a substance or treatment of no intended therapeutic value.
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.
Platinum hexafluoride is the chemical compound with the formula PtF6.
Pneumonia is an inflammatory condition of the lung affecting primarily the small air sacs known as alveoli.
Wydawnictwo Naukowe PWN (Polish Scientific Publishers PWN; until 1991 Państwowe Wydawnictwo Naukowe - National Scientific Publishers PWN, PWN) is a Polish book publisher, founded in 1951.
Polyester is a category of polymers that contain the ester functional group in their main chain.
Positron emission or beta plus decay (β+ decay) is a subtype of radioactive decay called beta decay, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino (νe).
Potassium nitrate is a chemical compound with the chemical formula KNO3.
Pressure swing adsorption (PSA) is a technology used to separate some gas species from a mixture of gases under pressure according to the species' molecular characteristics and affinity for an adsorbent material.
Preterm birth, also known as premature birth, is the birth of a baby at fewer than 37 weeks gestational age.
Proteins are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues.
A protoplanetary disk is a rotating circumstellar disk of dense gas and dust surrounding a young newly formed star, a T Tauri star, or Herbig Ae/Be star.
A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs.
Pulmonary fibrosis (literally "scarring of the lungs") is a respiratory disease in which scars are formed in the lung tissues, leading to serious breathing problems.
The factors that determine the values for alveolar pO2 and pCO2 are.
Pyrotechnics is the science of using materials capable of undergoing self-contained and self-sustained exothermic chemical reactions for the production of heat, light, gas, smoke and/or sound.
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.
Quartz is a mineral composed of silicon and oxygen atoms in a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2.
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.
Raoul-Pierre Pictet (4 April 1846 – 27 July 1929) was a Swiss physicist.
Rayleigh scattering (pronounced), named after the British physicist Lord Rayleigh (John William Strutt), is the (dominantly) elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation.
Reactive oxygen species (ROS) are chemically reactive chemical species containing oxygen.
A rebreather is a breathing apparatus that absorbs the carbon dioxide of a user's exhaled breath to permit the rebreathing (recycling) of the substantially unused oxygen content, and unused inert content when present, of each breath.
Red blood cells-- also known as RBCs, red cells, red blood corpuscles, haematids, erythroid cells or erythrocytes (from Greek erythros for "red" and kytos for "hollow vessel", with -cyte translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system.
Redox (short for reduction–oxidation reaction) (pronunciation: or) is a chemical reaction in which the oxidation states of atoms are changed.
Reflectance of the surface of a material is its effectiveness in reflecting radiant energy.
Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object and thus in contrast to on-site observation.
In chemistry residue is whatever remains or acts as a contaminant after a given class of events.
In physiology, respiration is defined as the movement of oxygen from the outside environment to the cells within tissues, and the transport of carbon dioxide in the opposite direction.
The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants.
Robert Boyle (25 January 1627 – 31 December 1691) was an Anglo-Irish natural philosopher, chemist, physicist, and inventor.
Robert Hutchings Goddard (October 5, 1882 – August 10, 1945) was an American engineer, professor, physicist, and inventor who is credited with creating and building the world's first liquid-fueled rocket.
Robert Hooke FRS (– 3 March 1703) was an English natural philosopher, architect and polymath.
Rock or stone is a natural substance, a solid aggregate of one or more minerals or mineraloids.
A rocket engine uses stored rocket propellant mass for forming its high-speed propulsive jet.
Rocket propellant is a material used either directly by a rocket as the reaction mass (propulsive mass) that is ejected, typically with very high speed, from a rocket engine to produce thrust, and thus provide spacecraft propulsion, or indirectly to produce the reaction mass in a chemical reaction.
The Royal Society of Chemistry (RSC) is a learned society (professional association) in the United Kingdom with the goal of "advancing the chemical sciences".
Rust is an iron oxide, a usually red oxide formed by the redox reaction of iron and oxygen in the presence of water or air moisture.
The Schumann–Runge bands are a set of absorption bands of molecular oxygen that occur at wavelengths between 176 and 192.6 nanometres.
Scuba diving is a mode of underwater diving where the diver uses a self-contained underwater breathing apparatus (scuba) which is completely independent of surface supply, to breathe underwater.
Seawater, or salt water, is water from a sea or ocean.
Michael Sendivogius (Michał Sędziwój; 1566–1636) was a Polish alchemist, philosopher, and medical doctor.
Signal-to-noise ratio (abbreviated SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise.
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.
Silicate minerals are rock-forming minerals with predominantly silicate anions.
Silicon is a chemical element with symbol Si and atomic number 14.
Silicon dioxide, also known as silica (from the Latin silex), is an oxide of silicon with the chemical formula, most commonly found in nature as quartz and in various living organisms.
Singlet oxygen, systematically named dioxygen(singlet) and dioxidene, is a gaseous inorganic chemical with the formula O.
The skeleton is the body part that forms the supporting structure of an organism.
Smelting is a process of applying heat to ore in order to melt out a base metal.
Smog is a type of air pollutant.
Sodium chlorate is an inorganic compound with the chemical formula NaClO3.
The Solar SystemCapitalization of the name varies.
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona.
Solid oxygen forms at normal atmospheric pressure at a temperature below 54.36 K (−218.79 °C, −361.82 °F).
Solubility is the property of a solid, liquid or gaseous chemical substance called solute to dissolve in a solid, liquid or gaseous solvent.
A solvent (from the Latin solvō, "loosen, untie, solve") is a substance that dissolves a solute (a chemically distinct liquid, solid or gas), resulting in a solution.
A space suit is a garment worn to keep a human alive in the harsh environment of outer space, vacuum and temperature extremes.
Spiders (order Araneae) are air-breathing arthropods that have eight legs and chelicerae with fangs that inject venom.
In quantum mechanics and particle physics, spin is an intrinsic form of angular momentum carried by elementary particles, composite particles (hadrons), and atomic nuclei.
Sport (British English) or sports (American English) includes all forms of competitive physical activity or games which, through casual or organised participation, aim to use, maintain or improve physical ability and skills while providing enjoyment to participants, and in some cases, entertainment for spectators.
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.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
Steel is an alloy of iron and carbon and other elements.
A submarine (or simply sub) is a watercraft capable of independent operation underwater.
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.
The Sun is the star at the center of the Solar System.
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic flux fields occurring in certain materials, called superconductors, when cooled below a characteristic critical temperature.
A superoxide is a compound that contains the superoxide anion, which has the chemical formula.
Surface-supplied diving is diving using equipment supplied with breathing gas using a diver's umbilical from the surface, either from the shore or from a diving support vessel, sometimes indirectly via a diving bell.
Tetrahydrofuran (THF) is an organic compound with the formula (CH2)4O.
The tetraoxygen molecule (O4), also called oxozone, was first predicted in 1924 by Gilbert N. Lewis, who proposed it as an explanation for the failure of liquid oxygen to obey Curie's law.
A textile is a flexible material consisting of a network of natural or artificial fibres (yarn or thread).
The Botanic Garden (1791) is a set of two poems, The Economy of Vegetation and The Loves of the Plants, by the British poet and naturalist Erasmus Darwin.
The New York Times (sometimes abbreviated as The NYT or The Times) is an American newspaper based in New York City with worldwide influence and readership.
A thylakoid is a membrane-bound compartment inside chloroplasts and cyanobacteria.
Tin is a chemical element with the symbol Sn (from stannum) and atomic number 50.
Titanium is a chemical element with symbol Ti and atomic number 22.
In chemistry, the term transition metal (or transition element) has three possible meanings.
Dioxygen complexes are coordination compounds that contain O2 as a ligand.
The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon.
Triplet oxygen, 3O2, refers to the S.
In quantum mechanics, a triplet is a quantum state of a system with a spin of quantum number s.
The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place.
Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.
Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment.
Uppsala (older spelling Upsala) is the capital of Uppsala County and the fourth largest city of Sweden, after Stockholm, Gothenburg and Malmö.
Vacuum swing adsorption (VSA) is a non-cryogenic gas separation technology.
In molecular physics, the van der Waals forces, named after Dutch scientist Johannes Diderik van der Waals, are distance-dependent interactions between atoms or molecules.
Veins are blood vessels that carry blood toward the heart.
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days.
Vertebrates comprise all species of animals within the subphylum Vertebrata (chordates with backbones).
Water is a transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms.
Water pollution is the contamination of water bodies, usually as a result of human activities.
Water treatment is any process that improves the quality of water to make it more acceptable for a specific end-use.
Wave–particle duality is the concept in quantum mechanics that every particle or quantic entity may be partly described in terms not only of particles, but also of waves.
Wüstite (FeO) is a mineral form of iron(II) oxide found with meteorites and native iron.
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing fusion, which is distinct from lower temperature metal-joining techniques such as brazing and soldering, which do not melt the base metal.
Wiltshire is a county in South West England with an area of.
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants.
Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents and catalysts.
Zirconium dioxide, sometimes known as zirconia (not to be confused with zircon), is a white crystalline oxide of zirconium.
Zygmunt Florenty Wróblewski (28 October 1845 – 16 April 1888) was a Polish physicist and chemist.
1,4-Dioxane is a heterocyclic organic compound, classified as an ether.
ATC code V03AN01, ATCvet code QV03AN01, Active oxygen, Atomic number 8, Diatomic Oxygen, Diatomic oxide, Dioxygen molecule, E948, Element 8, Free oxygen, History of oxygen, O (element), Oxigen, Oxygen Atom, Oxygen atom, Oxygen gas, Oxygen ion, Oxygen partial pressure, Oxygen rings, Oxygyn, O₂, Pure oxygen, Sauerstoff, Vital air.