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| Name, symbol, number | oxygen, O, 8 | ||||||||||||||||||||||||
| Chemical series | nonmetals, chalcogens | ||||||||||||||||||||||||
| Group, period, block | 16, 2, p | ||||||||||||||||||||||||
| Appearance |
 Liquid Oxygen |
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| Standard atomic weight | 15.9994(3) g·mol−1 | ||||||||||||||||||||||||
| Electron configuration | 1s2 2s2 2p4 | ||||||||||||||||||||||||
| Electrons per shell | 2, 6 | ||||||||||||||||||||||||
| Physical properties | |||||||||||||||||||||||||
| Phase | gas | ||||||||||||||||||||||||
| Melting point | 54. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Fluorine, fluorum meaning "to flow" is the Chemical element with the symbol F and Atomic number 9 Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 This is a typical display of the periodic table of the elements and contains the symbol and Atomic number of each element Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of Chemical elements, sorted by name Wikipedia talkFeatured lists for an explanation of this and other inclusion tags below -->This is a list of chemical elements by symbol, including the A table of Chemical elements ordered by Atomic number and color coded according to type of element In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in Nonmetal is a term used in Chemistry when classifying the Chemical elements On the basis of their general physical and chemical properties every element in the See also Gold chalcogenides Periodic table In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in In the Periodic table of the elements, a period is a horizontal row of the table A block of the Periodic table of elements is a set of adjacent groups The respective highest-energy electrons in each element in a block belong to the same Atomic See also Gold chalcogenides Periodic table A period 2 element is one of the Chemical elements in the second row (or period) of the periodic table of the chemical elements. See also Electron configuration The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass To help compare different orders of magnitude, the following list describes various Mass levels between 10&minus36&thinsp kg and 1053&thinspkg Molar mass, symbol M, is the Mass of one mole of a substance ( Chemical element or Chemical compound) In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J An electron shell may be crudely thought of as an Orbit followed by Electrons around an Atom nucleus. In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties This page is about the physical properties of gas as a state of matter The melting point of a solid is the temperature range at which it changes state from solid to Liquid. 36 K (-218. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 79 °C, -361. The Celsius Temperature scale was previously known as the centigrade scale. 82 °F) |
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| Boiling point | 90. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid 20 K (-182. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 95 °C, -297. The Celsius Temperature scale was previously known as the centigrade scale. 31 °F) |
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| Critical point | 154. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 In Physical chemistry, Thermodynamics, Chemistry and Condensed matter physics, a critical point, also called a critical state 59 K, 5. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 043 MPa | ||||||||||||||||||||||||
| Heat of fusion | (O2) 0. The standard Enthalpy of fusion (symbol \Delta{}H_{fus} also known as the heat of fusion or specific melting heat, is the amount of 444 kJ·mol−1 | ||||||||||||||||||||||||
| Heat of vaporization | (O2) 6. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material The enthalpy of vaporization, (symbol \Delta{}_{v}H also known as the heat of vaporization or heat of evaporation, is the Energy required 82 kJ·mol−1 | ||||||||||||||||||||||||
| Specific heat capacity | (25 °C) (O2) 29. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the Temperature of a unit quantity 378 J·mol−1·K−1 |
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| Atomic properties | |||||||||||||||||||||||||
| Crystal structure | cubic | ||||||||||||||||||||||||
| Oxidation states | 2, 1, −1, −2 (neutral oxide) |
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| Electronegativity | 3. Vapor pressure (also known as equilibrium vapor pressure or saturation vapor pressure) is the Pressure of a Vapor in equilibrium In Mineralogy and Crystallography, a crystal structure is a unique arrangement of Atoms in a Crystal. The oxidation number of a central atom in a coordination compound is the charge that it would have if all the Ligands were removed along with the Electron pairs Oxygen difluoride is the Chemical compound with the formula OF2 Dioxygen difluoride is a compound with the formula O2F2 This yellow compound is a strong oxidant and decomposes into OF2 and oxygen A peroxide is a compound containing an Oxygen -oxygen single bond. " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons 44 (Pauling scale) | ||||||||||||||||||||||||
| Ionization energies (more) |
1st: 1313. The ionization potential, ionization energy or EI of an Atom or Molecule is the Energy required to remove an Electron These tables list the Ionization energy in kJ/mol necessary to remove one mole of Electrons from one mole of neutral gaseous Atoms (first energy respectively 9 kJ·mol−1 | ||||||||||||||||||||||||
| 2nd: 3388. The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material 3 kJ·mol−1 | |||||||||||||||||||||||||
| 3rd: 5300. 5 kJ·mol−1 | |||||||||||||||||||||||||
| Atomic radius | 60 pm | ||||||||||||||||||||||||
| Atomic radius (calc. Atomic radius, and more generally the size of an atom, is not a precisely defined Physical quantity, nor is it constant in all circumstances A picometre ( American spelling: picometer, symbol pm) is a unit of Length in the Metric system, equal to one trillionth ) | 48 pm | ||||||||||||||||||||||||
| Covalent radius | 73 pm | ||||||||||||||||||||||||
| Van der Waals radius | 152 pm | ||||||||||||||||||||||||
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| Magnetic ordering | paramagnetic | ||||||||||||||||||||||||
| Thermal conductivity | (300 K) 26. The covalent radius, r cov is a measure of the size of Atom which forms part of a Covalent bond. Van der Waals Volume The van der Waals volume, V, also called the atomic volume or molecular volume, is the atomic property most directly In Physics, magnetism is one of the Phenomena by which Materials exert attractive or repulsive Forces on other Materials. Paramagnetism is a form of magnetism which occurs only in the presence of an externally applied magnetic field In Physics, thermal conductivity, k is the property of a material that indicates its ability to conduct Heat. 58x10-3 W·m−1·K−1 | ||||||||||||||||||||||||
| Speed of sound | (gas, 27 °C) 330 m/s | ||||||||||||||||||||||||
| CAS registry number | 7782-44-7 | ||||||||||||||||||||||||
| Selected isotopes | |||||||||||||||||||||||||
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Oxygen is the element with atomic number 8 and represented by the symbol O. Oxygen-18 ( 18O) is a natural stable Isotope of Oxygen and one of the Environmental isotopes. Oxygen-18 ( 18O) is a natural stable Isotope of Oxygen and one of the Environmental isotopes. Stable isotopes are chemical isotopes that are not Radioactive (to current knowledge This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. Recommended values for many properties of the elements together with various references are collected on these data pages A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus. See also List of elements by atomic number In Chemistry and Physics, the atomic number (also known as the proton It is a member of the chalcogen group on the periodic table, and is a highly reactive nonmetallic period 2 element that readily forms compounds (notably oxides) with almost all other elements. See also Gold chalcogenides Periodic table In Chemistry a group, also known as a family, is a vertical column in the Periodic table of the Chemical elements There are 18 groups in The periodic table of the chemical elements is a tabular method of displaying the Chemical elements Although precursors to this table exist its invention is Nonmetal is a term used in Chemistry when classifying the Chemical elements On the basis of their general physical and chemical properties every element in the A period 2 element is one of the Chemical elements in the second row (or period) of the periodic table of the chemical elements. A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element At standard temperature and pressure two atoms of the element bind to form dioxygen, a colorless, odorless, tasteless diatomic gas with the formula O2. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic Diatomic molecules are molecules made only of two Atoms of either the same or different Chemical elements The prefix di- means two in Greek This page is about the physical properties of gas as a state of matter Oxygen is the third most abundant element in the universe by mass after hydrogen and helium[1] and the most abundant element by mass in the Earth's crust. See also Abundances of the elements (data page The abundance of a Chemical element measures how relatively common the element is or how much of the element Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Helium ( He) is a colorless odorless tasteless non-toxic Inert Monatomic Chemical Chemical elements data references Earth bulk continental crust and upper continental crust C1 &mdash Crust CRC Handbook In Geology, a crust is the outermost solid shell of a planet or moon [2] Oxygen constitutes 88. 8% of the mass of water and 20. 9% of the volume of air. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five [3]
All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl Carbohydrates (from ' Hydrates of Carbon ' or saccharides ( Greek σάκχαρον meaning " Sugar " are the most Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water Traditionally inorganic compounds are considered to be of mineral not biological origin Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all complex life. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Cellular respiration is the set of the metabolic reactions and processes that take place in Organisms cells to convert biochemical energy from Oxygen is toxic to anaerobic organisms, which were the dominant form of early life on Earth until O2 began to accumulate in the atmosphere 2. An anaerobic organism is any Organism that does not require Oxygen for growth and may even die in its presence Although evidence of early Life is scarce and often difficult to interpret it appears that life appeared on Earth relatively soon (on the Geologic time scale) after 5 billion years ago. [4] Another form (allotrope) of oxygen, ozone (O3), helps protect the biosphere from ultraviolet radiation with the high-altitude ozone layer, but is a pollutant near the surface where it is a by-product of smog. There are several known Allotropes of oxygen Dioxygen, O2 - colorless Ozone, O3 - blue Tetraoxygen OZONE is an object oriented Operating system written in the C programming language. Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays The photochemical mechanisms that give rise to the ozone layer were worked out by the British physicist Sidney Chapman in 1930 Smog is a kind of Air pollution; the word "smog" is a Portmanteau of Smoke and Fog.
Oxygen was independently discovered by Joseph Priestley in Wiltshire, in 1774, and Carl Wilhelm Scheele, in Uppsala, a year earlier, but Priestley is usually given priority because he published his findings first. Joseph Priestley (13 March 1733 ( Old Etymology The county formerly 'Wiltonshire' or 'Wiltunscir' (9th century is named after the former county town of Wilton (itself named after the River Wylye Carl Wilhelm Scheele (9 December 1742 &ndash 21 May 1786 was a German - Swedish pharmaceutical chemist born in Stralsund, Western Pomerania, Uppsala ˈɵpˌsɑːla (older spelling Upsala) is the capital of Uppsala County ( Uppsala län) and the fourth largest city of The name oxygen was coined in 1777 by Antoine Lavoisier,[5] whose experiments with oxygen helped to discredit the then-popular phlogiston theory of combustion and corrosion. The phlogiston theory (from the Ancient Greek φλογιστόν phlŏgistón "burning up" from φλόξ phlóx "fire" first stated Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of Corrosion means the breaking down of essential properties in a material due to Chemical reactions with its surroundings Oxygen is produced industrially by fractional distillation of liquefied air, use of zeolites to remove carbon dioxide and nitrogen from air, electrolysis of water and other means. Fractional distillation is the separation of a mixture into its component parts or fractions such as in separating Chemical compounds by their Boiling point by heating Zeolites (Greek zein, "to boil" lithos, "a stone" are hydrated Aluminosilicate Minerals and have a micro-porous structure Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Electrolysis of water is the decomposition of Water (H2O into Oxygen (O2 and Hydrogen gas (H2 Uses of oxygen include the production of steel, plastics and textiles; rocket propellant; oxygen therapy; and life support in aircraft, submarines, spaceflight and diving. Rocket propellant is mass that is stored usually in some form of Propellant tank prior to being used as the propulsive mass that is ejected from a rocket engine in the form Oxygen therapy is the administration of Oxygen as a therapeutic modality A human spaceflight is a Spaceflight with a human crew, and possibly passengers This article refers to underwater diving by humans For other uses of the term diving see Dive and Diving Underwater diving is
Contents |
Characteristics
Structure
At standard temperature and pressure, oxygen is a colorless, odorless gas with the molecular formula O2, in which the two oxygen atoms are chemically bonded to each other with a spin triplet electron configuration. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic In Physics, '''spin''' is the Angular momentum intrinsic to a body as opposed to Orbital angular momentum, which is the motion of its Center of mass In Atomic physics and Quantum chemistry, electron configuration is the arrangement of Electrons in an Atom, Molecule, or other This bond has a bond order of two, and is often simplified in description as a double bond[6] or as a combination of one two-electron bond and two three-electron bonds. Bond order is the number of bonds between a pair of atoms For example in Nitrogen N≡N the bond order is 3 in Acetylene H−C≡C−H the bond order between the A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic [7]
Triplet oxygen is the ground state of the O2 molecule. Triplet oxygen is the Ground state of the Oxygen molecule The Electron configuration of the molecule has two unpaired electrons occupying two degenerate In Quantum mechanics, a stationary state is an Eigenstate of a Hamiltonian, or in other words a state of definite energy [8] The electron configuration of the molecule has two unpaired electrons occupying two degenerate molecular orbitals. See also Degenerate energy level Degenerate orbitals for Electrons in an Atomic subshell are orbitals at identical energy levels In Chemistry, a molecular orbital (or MO) is a region in which an Electron may be found in a Molecule. [9] These orbitals are classified as antibonding (weakening the bond order from three to two), so the diatomic oxygen bond is weaker than the diatomic nitrogen triple bond in which all bonding molecular orbitals are filled, but some antibonding orbitals are not. Antibonding (or anti-bonding) is a type of chemical bonding. An antibonding orbital is a form of Molecular orbital (MO that is located outside the region Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 [8]
In normal triplet form, O2 molecules are paramagnetic—they form a magnet in the presence of a magnetic field—because of the spin magnetic moments of the unpaired electrons in the molecule, and the negative exchange energy between neighboring O2 molecules. Paramagnetism is a form of magnetism which occurs only in the presence of an externally applied magnetic field In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin In Physics, Astronomy, Chemistry, and Electrical engineering, the term magnetic moment of a system (such as a loop of Electric current In Physics, the exchange interaction is a Quantum mechanical effect which increases or decreases the expectation value of the Energy or Distance [10] Liquid oxygen is attracted to a magnet to a sufficient extent that, in laboratory demonstrations, a bridge of liquid oxygen may be supported against its own weight between the poles of a powerful magnet. A magnet (from Greek grc μαγνήτης λίθος " Magnesian stone" is a material or object that produces a Magnetic field. [11][12]
Singlet oxygen, a name given to several higher-energy species of molecular O2 in which all the electron spins are paired, is much more reactive towards common organic molecules. Singlet oxygen is the common name used for the two Metastable states of molecular Oxygen (O2 with higher energy than the ground state Triplet oxygen An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. In nature, singlet oxygen is commonly formed from water during photosynthesis, using the energy of sunlight. [13] It is also produced in the troposphere by the photolysis of ozone by light of short wavelength,[14] and by the immune system as a source of active oxygen. The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 75% of the atmosphere's mass and almost all of its Water vapor and [15] Carotenoids in photosynthetic organisms (and possibly also in animals) play a major role in absorbing energy from singlet oxygen and converting it to the unexcited ground state before it can cause harm to tissues. Carotenoids are organic Pigments that are naturally occurring in Chromoplasts of plants and some other photosynthetic Organisms [16]
Allotropes
The common allotrope of elemental oxygen on Earth is called dioxygen, O2. Allotropy (Gr allos, other and tropos, manner is a behavior exhibited by certain Chemical elements these elements can exist in two or more different It has a bond length of 121 pm and a bond energy of 498 kJ·mol-1. A picometre ( American spelling: picometer, symbol pm) is a unit of Length in the Metric system, equal to one trillionth The joule per mole (symbol J·mol-1 is an SI derived unit of energy per amount of material [17] This is the form that is used by complex forms of life, such as animals, in cellular respiration (see Biological role) and is the form that is a major part of the Earth's atmosphere (see Occurrence). Cellular respiration is the set of the metabolic reactions and processes that take place in Organisms cells to convert biochemical energy from Other aspects of O2 are covered in the remainder of this article.
Trioxygen (O3) is usually known as ozone and is a very reactive allotrope of oxygen that is damaging to lung tissue. OZONE is an object oriented Operating system written in the C programming language. [18] Ozone is produced in the upper atmosphere when O2 combines with atomic oxygen made by the splitting of O2 by ultraviolet (UV) radiation. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five Ultraviolet ( UV) light is Electromagnetic radiation with a Wavelength shorter than that of Visible light, but longer than X-rays [5] Since ozone absorbs strongly in the UV region of the spectrum, it functions as a protective radiation shield for the planet (see ozone layer). The electromagnetic (EM spectrum is the range of all possible Electromagnetic radiation frequencies The photochemical mechanisms that give rise to the ozone layer were worked out by the British physicist Sidney Chapman in 1930 [5] Near the earth's surface, however, it is a pollutant formed as a by-product of automobile exhaust. Air pollution is the human introduction into the atmosphere of Chemicals Particulate matter, or Biological materials that cause harm or discomfort [19]
The metastable molecule tetraoxygen (O4) was discovered in 2001,[20][21] and was assumed to exist in one of the six phases of solid oxygen. Metastability is a general scientific concept which describes states of delicate equilibrium O4 is also a subclass of O- class stars. The tetraoxygen molecule (O4 also called oxozone was first predicted in 1924 by Solid oxygen forms at normal Atmospheric pressure at a temperature below 54 It was proven in 2006 that that phase, created by pressurizing O2 to 20 GPa, is in fact a rhombohedral O8 cluster. In Crystallography, the rhombohedral (or trigonal) Crystal system is one of the seven lattice point groups named after the two-dimensional In Chemistry, a cluster is an ensemble of bound Atoms intermediate in size between a Molecule and a bulk Solid. [22] This cluster has the potential to be a much more powerful oxidizer than either O2 or O3 and may therefore be used in rocket fuel. An oxidizing agent or oxidising agent (also called an oxidant, oxidizer or oxidiser) can be defined as either a Chemical compound Rocket propellant is mass that is stored usually in some form of Propellant tank prior to being used as the propulsive mass that is ejected from a rocket engine in the form [20][21] A metallic phase was discovered in 1990 when solid oxygen is subjected to a pressure of above 96 GPa[23] and it was shown in 1998 that at very low temperatures, this phase becomes superconducting. Superconductivity is a phenomenon occurring in certain Materials generally at very low Temperatures characterized by exactly zero electrical resistance [24]
Physical properties
- See also: Liquid oxygen and solid oxygen
Oxygen is more soluble in water than nitrogen; water contains approximately 1 molecule of O2 for every 2 molecules of N2, compared to an atmospheric ratio of approximately 1:4. Solid oxygen forms at normal Atmospheric pressure at a temperature below 54 Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. The solubility of oxygen in water is temperature-dependent, and about twice as much (14. 6 mg·L−1) dissolves at 0 °C than at 20 °C (7. 6 mg·L−1). [25][26] At 25 °C and 1 atm of air, freshwater contains about 6. The Standard atmosphere is an international reference pressure defined as 101325 Pa and formerly used as unit of Pressure (symbol atm 04 milliliters (mL) of oxygen per liter, whereas seawater contains about 4. The litre or liter (see spelling differences) is a unit of Volume. The litre or liter (see spelling differences) is a unit of Volume. Seawater is Water from a Sea or Ocean. On average seawater in the world's oceans has a Salinity of about 3 95 mL per liter. [27] At 5 °C the solubility increases to 9. 0 mL (50% more than at 25 °C) per liter for water and 7. 2 mL (45% more) per liter for sea water.
Oxygen condenses at 90. 20 K (−182. The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic 95 °C, −297. 31 °F), and freezes at 54. 36 K (−218. 79 °C, −361. 82 °F). [28] Both liquid and solid O2 are clear substances with a light sky-blue color caused by absorption in the red (in contrast with the blue color of the sky, which is due to Rayleigh scattering of blue light). Solid oxygen forms at normal Atmospheric pressure at a temperature below 54 Diffuse sky radiation is Solar radiation reaching the Earth 's surface after having been scattered from the direct solar beam by Molecules Rayleigh scattering (named after Lord Rayleigh) is the elastic Scattering of Light or other electromagnetic radiation by particles much smaller High-purity liquid O2 is usually obtained by the fractional distillation of liquefied air;[29] Liquid oxygen may also be produced by condensation out of air, using liquid nitrogen as a coolant. Fractional distillation is the separation of a mixture into its component parts or fractions such as in separating Chemical compounds by their Boiling point by heating It is a highly-reactive substance and must be segregated from combustible materials. [30]
Isotopes and stellar origin
Naturally occurring oxygen is composed of three stable isotopes, 16O, 17O, and 18O, with 16O being the most abundant (99. There are three stable isotopes of oxygen that lead to Oxygen ( O) having a standard atomic mass of 15 Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides Oxygen-18 ( 18O) is a natural stable Isotope of Oxygen and one of the Environmental isotopes. 762% natural abundance). In Chemistry, natural abundance (NA refers to the abundance Isotopes of a Chemical element as naturally found on a planet [31] Oxygen isotopes range in mass number from 12 to 28. The mass number ( A) also called atomic mass number or nucleon number, is the total number of Protons and Neutrons (together known as [31]
Most 16O is synthesized at the end of the helium fusion process in stars but some is made in the neon burning process. Nucleosynthesis is the process of creating new atomic nuclei from preexisting Nucleons (protons and neutrons Helium fusion is a kind of Nuclear fusion, with the nuclei involved being Helium. A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth The neon burning process is a set of Nuclear fusion reactions that take place in massive Stars (at least 8 MSun) [32] 17O is primarily made by the burning of hydrogen into helium during the CNO cycle, making it a common isotope in the hydrogen burning zones of stars. Helium ( He) is a colorless odorless tasteless non-toxic Inert Monatomic Chemical The CNO cycle (for Carbon - Nitrogen - Oxygen) or sometimes Bethe-Weizsäcker-cycle, is one of two sets of fusion reactions [32] Most 18O is produced when 14N (made abundant from CNO burning) captures a 4He nucleus, making 18O common in the helium-rich zones of stars. Nitrogen-14 is a stable, non- Radioactive Isotope of the Chemical element Nitrogen. Helium-4 ( or) is a non- Radioactive and light Isotope of Helium. [32]
Fourteen radioisotopes have been characterized, the most stable being 15O with a half-life of 122. A radionuclide is an Atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created Half-Life (computer-game page here It's already listed in the disambiguation page 24 seconds (s) and 14O with a half-life of 70. 606 s. [31] All of the remaining radioactive isotopes have half-lives that are less than 27 s and the majority of these have half-lives that are less than 83 milliseconds. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. [31] The most common decay mode of the isotopes lighter than 16O is electron capture to yield nitrogen, and the most common mode for the isotopes heavier than 18O is beta decay to yield fluorine. Radioactive decay is the process in which an unstable Atomic nucleus loses energy by emitting ionizing particles and Radiation. Electron capture (sometimes called inverse beta decay) is a Decay mode for Isotopes that will occur when there are too many Protons in the In Nuclear physics, beta decay is a type of Radioactive decay in which a Beta particle (an Electron or a Positron) is emitted Fluorine, fluorum meaning "to flow" is the Chemical element with the symbol F and Atomic number 9 [31]
Occurrence
- See also: Silicate minerals and Category:Oxide minerals
Oxygen is the most abundant chemical element, by mass, in our biosphere, air, sea and land. The silicate minerals make up the largest and most important class of rock-forming Minerals They are classified based on the structure of their silicate Ion group Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. [1] About 0. 9% of the Sun's mass is oxygen. The Sun (Sol is the Star at the center of the Solar System. [3] Oxygen constitutes 49. 2% of the Earth's crust by mass[2] and is the major component of the world's oceans (88. In Geology, a crust is the outermost solid shell of a planet or moon 8% by mass). [3] It is the second most common component of the Earth's atmosphere, taking up 21. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five 0% of its volume and 23. 1% of its mass (some 1015 tonnes). [33][3][34] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0. The Solar System consists of the Sun and those celestial objects bound to it by Gravity. 1% O2 by volume) and Venus have far lower concentrations. The VENUS ( V ictoria E xperimental N etwork U nder the S ea project is a cabled sea floor observatory operated by the University However, the O2 surrounding these other planets is produced solely by ultraviolet radiation impacting oxygen-containing molecules such as carbon dioxide. Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single
The unusually high concentration of oxygen on Earth is the result of the oxygen cycle. The oxygen cycle is the Biogeochemical cycle that describes the movement of Oxygen within and between its three main reservoirs the atmosphere (air the This biogeochemical cycle describes the movement of oxygen within and between its three main reservoirs on Earth: the atmosphere, the biosphere, and the lithosphere. In Ecology and Earth science, a biogeochemical cycle is a circuit or pathway by which a Chemical element or Molecule moves through both biotic The biosphere is the broadest level of ecological study the global sum of all Ecosystems. The lithosphere (IPA, from the Greek λίθος for "rocky" + σφαίρα for "sphere" is the solid outermost shell of a rocky Planet. The main driving factor of the oxygen cycle is photosynthesis, which is responsible for modern Earth's atmosphere. Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Because of the vast amounts of oxygen gas available in the atmosphere, even if all photosynthesis were to cease completely, it would take all the oxygen-consuming processes at the present rate at least another 5,000 years to strip all the O2 from the atmosphere. [35][36]
Free oxygen also occurs in solution in the world's water bodies. The increased solubility of O2 at lower temperatures (see Physical properties) has important implications for ocean life, as polar oceans support a much higher density of life due to their higher oxygen content. [37] Polluted water may have reduced amounts of O2 in it, depleted by decaying algae and other biomaterials (see eutrophication). Water pollution is the contamination of Water bodies such as Lakes Rivers Oceans and Groundwater caused by human activities Eutrophication is an increase in chemical Nutrients -- typically compounds containing Nitrogen or Phosphorus -- in an Ecosystem, and may occur Scientists assess this aspect of water quality by measuring the water's biochemical oxygen demand, or the amount of O2 needed to restore it to a normal concentration. Biochemical Oxygen Demand or Biological Oxygen Demand (BOD is a chemical procedure for determining how fast biological organisms use up oxygen in a body of water [38]
Biological role
Photosynthesis and respiration
In nature, free oxygen is produced by the light-driven splitting of water during oxygenic photosynthesis. Photodissociation, photolysis, or photodecomposition is a Chemical reaction in which a Chemical compound is broken down by Photons Photosynthesis is a Metabolic pathway that converts Light Energy into Chemical energy. Green algae and cyanobacteria in marine environments provide about 70% of the free oxygen produced on earth and the rest is produced by terrestrial plants. The green algae (singular green alga) are the large group of Algae from which the Embryophytes (higher plants emerged Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy [39]
A simplified overall formula for photosynthesis is:[40]
-
- 6CO2 + 6H2O + photons → C6H12O6 + 6O2 (or simply carbon dioxide + water + sunlight → glucose + dioxygen)
Photolytic oxygen evolution occurs in the thylakoid membranes of photosynthetic organisms and requires the energy of four photons. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena Oxygen evolution is the process of generating molecular Oxygen through Chemical reaction. A Thylakoid is a membrane-bound compartment inside Chloroplasts and cyanobacteria. In Physics, the photon is the Elementary particle responsible for electromagnetic phenomena [41] Many steps are involved, but the result is the formation of a proton gradient across the thylakoid membrane, which is used to synthesize ATP via photophosphorylation. The proton ( Greek πρῶτον / proton "first" is a Subatomic particle with an Electric charge of one positive Adenosine-5'-triphosphate ( ATP) is a multifunctional Nucleotide that is most important as a " molecular currency" of intracellular Energy The production of ATP using the energy of sunlight is called photophosphorylation. [42] The O2 remaining after oxidation of the water molecule is released into the atmosphere. [43]
Molecular dioxygen, O2, is essential for cellular respiration in all aerobic organisms. Cellular respiration is the set of the metabolic reactions and processes that take place in Organisms cells to convert biochemical energy from An aerobic organism or aerobe is an Organism that has an Oxygen based Metabolism. Oxygen is used in mitochondria to help generate adenosine triphosphate (ATP) during oxidative phosphorylation. In Cell biology, a mitochondrion (plural mitochondria) is a membrane-enclosed Organelle found in most eukaryotic cells. Adenosine-5'-triphosphate ( ATP) is a multifunctional Nucleotide that is most important as a " molecular currency" of intracellular Energy Oxidative phosphorylation is a Metabolic pathway that uses energy released by the oxidation of Nutrients to produce Adenosine triphosphate (ATP The reaction for aerobic respiration is essentially the reverse of photosynthesis and is simplified as:
-
- C6H12O6 + 6O2 → 6CO2 + 6H2O + 2880 kJ·mol-1
In vertebrates, O2 is diffused through membranes in the lungs and into red blood cells. Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes Diffusion is the net movement of particles (typically molecules from an area of high concentration to an area of low concentration by uncoordinated random movement Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood Hemoglobin binds O2, changing its color from bluish red to bright red. Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein [44][18] Other animals use hemocyanin (molluscs and some arthropods) or hemerythrin (spiders and lobsters). Hemocyanins (also spelled haemocyanins) are respiratory Proteins in the form of Metalloproteins containing two Copper atoms that reversibly Molluscs are animals belonging to the phylum Mollusca. There are around 250000 extant Species within the phylum with an estimated 70000 Arthropods are Animals belonging to the Phylum Arthropoda (from Greek ἄρθρον arthron, " Joint " Hemerythrin (also spelled haemerythrin; from Greek words αίμα = blood and ερυθρός = red is an Oligomeric Protein responsible for Oxygen Spiders are Predatory Invertebrate Animals that have two body segments, eight legs no chewing mouth parts and no wings Clawed lobsters compose a family ( Nephropidae, sometimes also Homaridae) of large marine Crustaceans Lobsters are economically important as [33] A liter of blood can dissolve 200 cc of O2. [33]
Reactive oxygen species, such as superoxide ion (O2−) and hydrogen peroxide (H2O2), are dangerous by-products of oxygen use in organisms. Reactive oxygen species (ROS are ions or very small molecules that include Oxygen Ions free radicals, and Peroxides both inorganic and Superoxide is the Anion O2&minus It is important as the product of the one-electron reduction of Dioxygen, which occurs widely in nature Hydrogen peroxide (H2O2 is a very pale blue liquid which appears colorless in a dilute solution slightly more Viscous than water [33] Parts of the immune system of higher organisms, however, create peroxide, superoxide, and singlet oxygen to destroy invading microbes. An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor Reactive oxygen species also play an important role in the hypersensitive response of plants against pathogen attack. The hypersensitive response (HR is a mechanism used by Plants, to prevent the spread of Infection by Microbial Pathogens The HR is characterized [42]
An adult human in rest inhales 1. Breathing takes Oxygen in and Carbon dioxide out of the body Aerobic Organisms require oxygen to create energy via respiration, in 8 to 2. 4 grams of oxygen per minute. [45] This amounts to more than 6 billion tonnes of oxygen inhaled by humanity per year. [46]
Build-up in the atmosphere
Free oxygen gas was almost nonexistent in Earth's atmosphere before photosynthetic archaea and bacteria evolved. Temperature and layers The temperature of the Earth's atmosphere varies with altitude the mathematical relationship between temperature and altitude varies among five The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have Free oxygen first appeared in significant quantities during the Paleoproterozoic era (between 2. The Paleoproterozoic (ˌpeɪlɪoʊˌproʊtərəˈzoʊɪk also spelled Palaeoproterozoic) is the first of the three sub-divisions ( eras) of the 5 and 1. 6 billion years ago). At first, the oxygen combined with dissolved iron in the oceans to form banded iron formations. Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 Banded iron formations (also known as banded ironstone formations or BIF s are a distinctive type of rock often found in primordial ( Precambrian) Sedimentary Free oxygen started to gas out of the oceans 2. 7 billion years ago, reaching 10% of its present level around 1. 7 billion years ago. [47]
The presence of large amounts of dissolved and free oxygen in the oceans and atmosphere may have driven most of the anaerobic organisms then living to extinction during the oxygen catastrophe about 2. An anaerobic organism is any Organism that does not require Oxygen for growth and may even die in its presence In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. The Oxygen Catastrophe was a massive environmental change believed to have happened during the Siderian period at the beginning of the Paleoproterozoic 4 billion years ago. However, cellular respiration using O2 enables aerobic organisms to produce much more ATP than anaerobic organisms, helping the former to dominate Earth's biosphere. Cellular respiration is the set of the metabolic reactions and processes that take place in Organisms cells to convert biochemical energy from An aerobic organism or aerobe is an Organism that has an Oxygen based Metabolism. The biosphere is the broadest level of ecological study the global sum of all Ecosystems. [48] Photosynthesis and cellular respiration of O2 allowed for the evolution of eukaryotic cells and ultimately complex multicellular organisms such as plants and animals. Animals Plants fungi, and Protists are eukaryotes (juːˈkærɪɒt or -oʊt Organisms whose cells are organized into complex
Since the beginning of the Cambrian era 540 million years ago, O2 levels have fluctuated between 15% and 30% per volume. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with [49] Towards the end of the Carboniferous era (about 300 million years ago) atmospheric O2 levels reached a maximum of 35% by volume,[49] allowing insects and amphibians to grow much larger than today's species. The Carboniferous is a geologic period and system that extends from the end of the Devonian period about 359 Human activities, including the burning of 7 billion tonnes of fossil fuels each year have had very little effect on the amount of free oxygen in the atmosphere. This article is about the tonne or metric ton For other tons see Ton. Fossil fuels or mineral fuels are fossil source Fuels that is Hydrocarbons found within the top layer of the Earth’s crust. [10] At the current rate of photosynthesis it would take about 2,000 years to regenerate the entire O2 in the present atmosphere. [50]
History
Early experiments
One of the first known experiments on the relationship between combustion and air was conducted by the second century BCE Greek writer on mechanics, Philo of Byzantium. Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of The term ancient Greece refers to the period of Greek history lasting from the Greek Dark Ages ca Philo of Byzantium ( Greek: Φίλων ο Βυζάντιος ca In his work Pneumatica, Philo observed that inverting a vessel over a burning candle and surrounding the vessel's neck with water resulted in some water rising into the neck. [51] Philo incorrectly surmised that parts of the air in the vessel were converted into the classical element fire and thus were able to escape through pores in the glass. Many ancient philosophies used a set of archetypal classical "elements" to explain patterns in Nature. Fire has been an important part of many cultures and religions from pre-history to modern day and was vital to the development of civilization Many centuries later Leonardo da Vinci built on Philo's work by observing that a portion of air is consumed during combustion and respiration. Leonardo di ser Piero da Vinci ( April 15 1452 – May 2 1519 was an Italian Polymath, having been a scientist Mathematician, Engineer In Animal physiology, respiration is the transport of Oxygen from the outside air to the cells within tissues and the transport of Carbon dioxide [52]
In the late 17th century, Robert Boyle proved that air is necessary for combustion. Robert Boyle was a Natural philosopher, chemist physicist inventor and early Gentleman scientist, noted for his work in Physics and Chemistry English chemist John Mayow refined this work by showing that fire requires only a part of air that he called spiritus nitroaereus or just nitroaereus. John Mayow FRS (1641 - 1679 was a Chemist, Physician, and Physiologist who is remembered today for conducting early research into respiration [53] In one experiment he found that placing either a mouse or a lit candle in a closed container over water caused the water to rise and replace one-fourteenth of the air's volume before extinguishing the subjects. [54] From this he surmised that nitroaereus is consumed in both respiration and combustion. In Animal physiology, respiration is the transport of Oxygen from the outside air to the cells within tissues and the transport of Carbon dioxide
Mayow observed that antimony increased in weight when heated, and inferred that the nitroaereus must have combined with it. Antimony (IPA (Received Pronunciation, /ˈæntɪmoʊni/ (US is a Chemical element with the symbol Sb (stibium meaning "mark" and [53] He also thought that the lungs separate nitroaereus from air and pass it into the blood and that animal heat and muscle movement result from the reaction of nitroaereus with certain substances in the body. [53] Accounts of these and other experiments and ideas were published in 1668 in his work Tractatus duo in the tract "De respiratione". [54]
Phlogiston theory
Robert Hooke, Ole Borch, Mikhail Lomonosov, and Pierre Bayen all produced oxygen in experiments in the 17th century but none of them recognized it as an element. Robert Hooke, FRS (18 July 1635 – 3 March 1703 was an English Natural philosopher and Polymath who played an important role in the Ole Borch ( Jutland, 1626 – 1690 ( Latinized to Olaus Borrichius) was a Danish Scientist, Physician, Grammarian Mikhail Vasilyevich Lomonosov (Михаи́л Васи́льевич Ломоно́сов () was a Russian Polymath, scientist [25] This may have been in part due to the prevalence of the philosophy of combustion and corrosion called the phlogiston theory, which was then the favored explanation of those processes. Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of Corrosion means the breaking down of essential properties in a material due to Chemical reactions with its surroundings
Established in 1667 by the German alchemist J. J. Becher, and modified by the chemist Georg Ernst Stahl by 1731,[55] phlogiston theory stated that all combustible materials were made of two parts. Johann Joachim Becher (6 May 1635 &ndash October 1682 was a German Physician, alchemist, precursor of Chemistry, scholar and adventurer best Georg Ernst Stahl ( October 21, 1660 &ndash May 24, 1734) was a German Chemist and Physician. One part, called phlogiston, was given off when the substance containing it was burned, while the dephlogisticated part was thought to be its true form, or calx. Calx is a residual substance sometimes in the form of a fine powder that is left when a Metal or Mineral combusts or is calcinated due to heat [52]
Highly combustible materials that leave little residuum, such as wood or coal, were thought to be made mostly of phlogiston; whereas non-combustible substances that corrode, such as iron, contained very little. Air did not play a role in phlogiston theory, nor were any initial quantitative experiments conducted to test the idea; instead, it was based on observations of what happens when something burns, that most common objects appear to become lighter and seem to lose something in the process. [52] The fact that a substance like wood actually gains overall weight in burning was hidden by the buoyancy of the gaseous combustion products. Indeed one of the first clues that the phlogiston theory was incorrect was that metals, too, gain weight in rusting (when they were supposedly losing phlogiston).
Discovery
Oxygen was first discovered by Swedish pharmacist Carl Wilhelm Scheele. "Sverige" redirects here For other uses see Sweden (disambiguation and Sverige (disambiguation. Carl Wilhelm Scheele (9 December 1742 &ndash 21 May 1786 was a German - Swedish pharmaceutical chemist born in Stralsund, Western Pomerania, He had produced oxygen gas by heating mercuric oxide and various nitrates by about 1772. In Inorganic chemistry, a nitrate is a salt of Nitric acid with an Ion composed of one Nitrogen and three Oxygen atoms [52][3] Scheele called the gas 'fire air' because it was the only known supporter of combustion. He wrote an account of this discovery in a manuscript he titled Treatise on Air and Fire, which he sent to his publisher in 1775. However, that document was not published until 1777. [56]
In the meantime, an experiment was conducted by the British clergyman Joseph Priestley on August 1, 1774 focused sunlight on mercuric oxide (HgO) inside a glass tube, which liberated a gas he named 'dephlogisticated air'. The Kingdom of Great Britain, also known as the United Kingdom of Great Britain, was a State in northwest Europe, in existence from 1707 to 1800 Joseph Priestley (13 March 1733 ( Old Events 30 BC - Octavian (later known as Augustus enters Alexandria, Egypt, bringing it under the control of the Roman Year 1774 ( MDCCLXXIV) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a Mercury(II oxide, also called mercuric oxide, has a formula of Hg[[oxygen O]] and a formula weight of 216 [3] He noted that candles burned brighter in the gas and that a mouse was more active and lived longer while breathing it. After breathing the gas himself, he wrote: "The feeling of it to my lungs was not sensibly different from that of common air, but I fancied that my breast felt peculiarly light and easy for some time afterwards. "[25] Priestley published his findings in 1775 in a paper titled "An Account of Further Discoveries in Air" which was included in the second volume of his book titled Experiments and Observations on Different Kinds of Air. Experiments and Observations on Different Kinds of Air (1774–86 is a six-volume work published by eighteenth-century British Polymath Joseph Priestley [57][52] Because he had published his findings first, Priestley is usually given priority in the discovery.
The noted French chemist Antoine Laurent Lavoisier later claimed to have discovered the new substance independently. However, Priestley visited Lavoisier in October 1774 and told him about his experiment and how he liberated the new gas. Scheele also posted a letter to Lavoisier on September 30, 1774 that described his own discovery of the previously-unknown substance, but Lavoisier never acknowledged receiving it (a copy of the letter was found in Scheele's belongings after his death). Events 1399 - Henry IV is proclaimed King of England. 1744 - France and Spain defeat the Year 1774 ( MDCCLXXIV) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar (or a [56]
Lavoisier's contribution
What Lavoisier did indisputably do (although this was disputed at the time) was to conduct the first adequate quantitative experiments on oxidation and give the first correct explanation of how combustion works. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state [3] He used these and similar experiments, all started in 1774, to discredit the phlogiston theory and to prove that the substance discovered by Priestley and Scheele was a chemical element. A chemical element is a type of Atom that is distinguished by its Atomic number; that is by the number of Protons in its nucleus.
In one experiment, Lavoisier observed that there was no overall increase in weight when tin and air were heated in a closed container. Tin is a Chemical element with the symbol Sn (stannum and Atomic number 50 [3] He noted that air rushed in when he opened the container, which indicated that part of the trapped air had been consumed. He also noted that the tin had increased in weight and that increase was the same as the weight of the air that rushed back in. This and other experiments on combustion were documented in his book Sur la combustion en général, which was published in 1777. [3] In that work, he proved that air is a mixture of two gases; 'vital air', which is essential to combustion and respiration, and azote (Gk. ἄζωτον "lifeless"), which did not support either.
Lavoisier renamed 'vital air' to oxygène in 1777 from the Greek roots ὀξύς (oxys) (acid, literally "sharp," from the taste of acids) and -γενής (-genēs) (producer, literally begetter), because he mistook oxygen to be a constituent of all acids. The Ancient Greek language is the historical stage in the development of the Hellenic language family spanning the Archaic (c In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are [5] Azote later became nitrogen in English, although it has kept the name in French and several other European languages. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 [3]
Oxygen entered the English language despite opposition by English scientists and the fact that Priestley had priority. This is partly due to a poem praising the gas titled "Oxygen" in the popular book The Botanic Garden (1791) by Erasmus Darwin, grandfather of Charles Darwin. 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 (12 December 1731&ndash18 April 1802 was an English Physician, natural philosopher physiologist inventor and poet Charles Robert Darwin (February 12 1809 &ndash April 19 1882 was an English naturalist, who realised and demonstrated that all Species of life [56]
Later history
John Dalton's original atomic hypothesis assumed that all elements were monoatomic and that the atoms in compounds would normally have the simplest atomic ratios with respect to one another. A rocket or rocket vehicle is a Missile, Aircraft or other Vehicle which obtains Thrust by the reaction of the John Dalton FRS (6 September 1766 &ndash 27 July 1844 was an English Chemist, Meteorologist and Physicist. This article focuses on the historical models of the atom For a history of the study of how atoms combine to form molecules see History of the molecule. For example, Dalton assumed that water's formula was HO, giving the atomic mass of oxygen as 8 times that of hydrogen, instead of the modern value of about 16. The atomic mass (ma is the Mass of an atom most often expressed in unified atomic mass units The atomic mass may be considered to be the total mass [58] In 1805, Joseph Louis Gay-Lussac and Alexander von Humboldt showed that water is formed of two volumes of hydrogen and one volume of oxygen; and by 1811 Amedeo Avogadro had arrived at the correct interpretation of water's composition, based on what is now called Avogadro's law and the assumption of diatomic elemental molecules. Joseph Louis Gay-Lussac (also Louis Joseph Gay-Lussac, December 6, 1778 – May 9, 1850) was a French chemist (September 14 1769 &ndash May 6 1859 was a German naturalist and explorer, and the younger brother of the Prussian minister philosopher and linguist Lorenzo Romano Amedeo Carlo Avogadro di Quaregna e di Cerreto, Count of Quaregna and Cerreto was an Italian Savant. Avogadro's law ( Avogadro's Hypothesis, or Avogadro's Principle) is a Gas law named after Amedeo Avogadro, who in 1811 hypothesized [59][60]
By the late 19th century scientists realized that air could be liquefied, and its components isolated, by compressing and cooling it. Using a cascade method, Swiss chemist and physicist Raoul Pierre Pictet evaporated liquid sulfur dioxide in order to liquefy carbon dioxide, which in turn was evaporated to cool oxygen gas enough to liquefy it. In Chemical engineering, a cascade is a plant consisting of several similar stages with each processing the output from the previous stage Raoul-Pierre Pictet ( 4 April 1846 &ndash 27 July 1929) was a Swiss Physicist and the first person to liquefy nitrogen Evaporation is the process by which Molecules in a Liquid state (e Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single He sent a telegram on December 22, 1877 to the French Academy of Sciences in Paris announcing his discovery of liquid oxygen. Events 1790 - The Turkish fortress of Izmail is stormed and captured by Suvorov and his Russian armies Year 1877 ( MDCCCLXXVII) was a Common year starting on Monday (link will display the full calendar of the Gregorian calendar (or a Common The French Academy of Sciences ( French: Académie des sciences) is a Learned society, founded in 1666 by Louis XIV at the [61] Just two days later, French physicist Louis Paul Cailletet announced his own method of liquefying molecular oxygen. Louis-Paul Cailletet ( September 21, 1832 &ndash January 5, 1913) was a French Physicist and inventor [61] Only a few drops of the liquid were produced in either case so no meaningful analysis could be conducted.
In 1891 Scottish chemist James Dewar was able to produce enough liquid oxygen to study. Sir James Dewar FRS ( September 20, 1842 &ndash March 27, 1923) was a Scottish Chemist and Physicist [10] The first commercially-viable process for producing liquid oxygen was independently developed in 1895 by German engineer Carl von Linde and British engineer William Hampson. Professor Doctor Carl Paul Gottfried von Linde ( 11 June, 1842 - 16 November 1934) was a German engineer who developed Refrigeration Both men lowered the temperature of air until it liquefied and then distilled the component gases by boiling them off one at a time and capturing them. Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture [62] Later, in 1901, oxyacetylene welding was demonstrated for the first time by burning a mixture of acetylene and compressed O2. Welding is a fabrication process that joins materials usually Metals or Thermoplastics by causing coalescence. Acetylene ( IUPAC name ethyne), C2H2 is a Hydrocarbon belonging to the group of Alkynes It is the simplest of all alkynes This method of welding and cutting metal later became common. [62]
In 1923 the American scientist Robert H. Goddard became the first person to develop a rocket engine; the engine used gasoline for fuel and liquid oxygen as the oxidizer. Robert Hutchings Goddard, PhD ( October 5, 1882 &ndash August 10 1945 U A rocket engine is a Jet engine that uses only Propellant mass for forming its high speed propulsive jet. An oxidizing agent or oxidising agent (also called an oxidant, oxidizer or oxidiser) can be defined as either a Chemical compound Goddard successfully flew a small liquid-fueled rocket 56 m at 97 km/h on March 16, 1926 in Auburn, Massachusetts, USA. Events 597 BC - Babylonians capture Jerusalem, replace Jehoiachin with Zedekiah as king Year 1926 ( MCMXXVI) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar. Auburn is a town in Worcester County, Massachusetts, United States. [62][63]
Industrial production
- See also: Oxygen evolution and fractional distillation
Two major methods are employed to produce the 100 million tonnes of O2 extracted from air for industrial uses annually. Oxygen evolution is the process of generating molecular Oxygen through Chemical reaction. Fractional distillation is the separation of a mixture into its component parts or fractions such as in separating Chemical compounds by their Boiling point by heating [56] The most common method is to fractionally-distill liquefied air into its various components, with nitrogen N2 distilling as a vapor while oxygen O2 is left as a liquid. Fractional distillation is the separation of a mixture into its component parts or fractions such as in separating Chemical compounds by their Boiling point by heating Distillation is a method of separating Mixtures based on differences in their volatilities in a boiling liquid mixture [56]
The other major method of producing O2 gas involves passing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sieves, which absorbs the nitrogen and delivers a gas stream that is 90% to 93% O2. Zeolites (Greek zein, "to boil" lithos, "a stone" are hydrated Aluminosilicate Minerals and have a micro-porous structure [56] Simultaneously, nitrogen gas is released from the other nitrogen-saturated zeolite bed, by reducing the chamber operating pressure and diverting part of the oxygen gas from the producer bed through it, in the reverse direction of flow. After a set cycle time the operation of the two beds is interchanged, thereby allowing for a continuous supply of gaseous oxygen to be pumped through a pipeline. This is known as pressure swing adsorption. 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 Oxygen gas is increasingly obtained by these non-cryogenic technologies (see also the related vacuum swing adsorption). Cryogenics is often used incorrectly to refer to Cryonics, cryopreserving humans or animals Vacuum Swing Absorption (VSA is a non-cryogenic gas separation technology [64]
Oxygen gas can also be produced through electrolysis of water into molecular oxygen and hydrogen. Electrolysis of water is the decomposition of Water (H2O into Oxygen (O2 and Hydrogen gas (H2 A similar method is the electrocatalytic O2 evolution from oxides and oxoacids. An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element An oxoacid is an Acid which contains Oxygen. More specifically it is an acid which contains oxygen contains at least one other element Chemical catalysts can be used as well, such as in chemical oxygen generators or oxygen candles that are used as part of the life-support equipment on submarines, and are still part of standard equipment on commercial airliners in case of depressurization emergencies. A chemical oxygen generator is a device that releases Oxygen created by a Chemical reaction. Another air separation technology involves forcing air to dissolve through ceramic membranes based on zirconium dioxide by either high pressure or an electric current, to produce nearly pure O2 gas. The word ceramic is derived from the Greek word κεραμικός ( keramikos) Zirconia redirects here For the Sailor Moon character see Dead Moon Circus. [38]
In large quantities, the price of liquid oxygen in 2001 was approximately $0. 21/kg. [65] Since the primary cost of production is the energy cost of liquefying the air, the production cost will change as energy cost varies.
For reasons of economy oxygen is often transported in bulk as a liquid in specially-insulated tankers, since one litre of liquefied oxygen is equivalent to 840 liters of gaseous oxygen at atmospheric pressure and 20 °C. The litre or liter (see spelling differences) is a unit of Volume. The Celsius Temperature scale was previously known as the centigrade scale. [56] Such tankers are used to refill bulk liquid oxygen storage containers, which stand outside hospitals and other institutions with a need for large volumes of pure oxygen gas. Liquid oxygen is passed through heat exchangers, which convert the cryogenic liquid into gas before it enters the building. A heat exchanger is a device built for efficient Heat transfer from one medium to another whether the media are separated by a solid wall so that they never mix or the media Oxygen is also stored and shipped in smaller cylinders containing the compressed gas; a form that is useful in certain portable medical applications and oxy-fuel welding and cutting. An oxygen tank is a storage vessel for Oxygen, which is either held under Pressure in Gas cylinders or as Liquid oxygen in a Cryogenic Concerning a. " for the verdict on this matter --> Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding [56]
Applications
- See also: Breathing gas, Redox, and Combustion
Medical
Uptake of O2 from the air is the essential purpose of respiration, so oxygen supplementation is used in medicine. Air is the most common and only natural breathing gas. Other artificial gases either pure gases or mixtures of gases are used in breathing equipment and enclosed habitats such Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of An oxygen concentrator is a device used to provide Oxygen therapy to a Patient at substantially higher concentrations than those of ambient air used as Emphysema is a chronic obstructive Pulmonary disease ( COPD) formerly termed a chronic obstructive Lung disease (COLD In Animal physiology, respiration is the transport of Oxygen from the outside air to the cells within tissues and the transport of Carbon dioxide Medicine is the art and science of healing It encompasses a range of Health care practices evolved to maintain and restore Human Health by the Oxygen therapy is used to treat emphysema, pneumonia, some heart disorders, and any disease that impairs the body's ability to take up and use gaseous oxygen. Oxygen therapy is the administration of Oxygen as a therapeutic modality Emphysema is a chronic obstructive Pulmonary disease ( COPD) formerly termed a chronic obstructive Lung disease (COLD Pneumonia is an inflammatory illness of the Lung. Frequently it is described as lung Parenchyma / alveolar inflammation and abnormal A disease is an abnormal condition of an organism that impairs bodily functions and can be deadly [66] Treatments are flexible enough to be used in hospitals, the patient's home, or increasingly by portable devices. Oxygen tents were once commonly used in oxygen supplementation, but have since been replaced mostly by the use of oxygen masks or nasal cannulas. An oxygen tent consists in 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 An oxygen mask provides a method to transfer breathing Oxygen gas from a storage tank to the Lungs. The nasal cannula (NC is a device used in the Hospital, in a pre-hospital setting or at home to deliver supplemental Oxygen to a patient or person in need of extra
Hyperbaric (high-pressure) medicine uses special oxygen chambers to increase the partial pressure of O2 around the patient and, when needed, the medical staff. Hyperbaric medicine, also known as hyperbaric oxygen therapy (HBOT is the medical use of Oxygen at a higher than Atmospheric pressure. Hyperbaric medicine, also known as hyperbaric oxygen therapy (HBOT is the medical use of Oxygen at a higher than Atmospheric pressure. In a mixture of Ideal gases each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume Carbon monoxide poisoning, gas gangrene, and decompression sickness (the 'bends') are sometimes treated using these devices. Carbon monoxide poisoning occurs after the inhalation of Carbon monoxide gas Gas gangrene is a Bacterial Infection that produces Gas within tissues in Gangrene. Decompression sickness (DCS, the diver’s disease, the bends, caisson disease is the name given to a variety of symptoms suffered by a person Increased O2 concentration in the lungs helps to displace carbon monoxide from the heme group of hemoglobin. Carbon monoxide, with the chemical formula CO is a colorless odorless tasteless yet highly toxic Gas. Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein Oxygen gas is poisonous to the anaerobic bacteria that cause gas gangrene, so increasing its partial pressure helps kill them. An anaerobic organism is any Organism that does not require Oxygen for growth and may even die in its presence Decompression sickness occurs in divers who decompress too quickly after a dive, resulting in bubbles of inert gas, mostly nitrogen and argon, forming in their blood. Increasing the pressure of O2 as soon as possible is part of the treatment. [66]
Oxygen is also used medically for patients who require mechanical ventilation, often at concentrations above the 21% found in ambient air. In Medicine, mechanical ventilation is a method to mechanically assist or replace spontaneous breathing when patients cannot do so on their own
Life support and recreational use
A notable application of O2 as a low-pressure breathing gas is in modern space suits, which surround their occupant's body with pressurized air. A space suit is a complex system of Garments equipment and environmental systems designed to keep a person alive and comfortable in the harsh environment of outer space Air is the most common and only natural breathing gas. Other artificial gases either pure gases or mixtures of gases are used in breathing equipment and enclosed habitats such A space suit is a complex system of Garments equipment and environmental systems designed to keep a person alive and comfortable in the harsh environment of outer space These devices use nearly pure oxygen at about one third normal pressure, resulting in a normal blood partial pressure of O2. In a mixture of Ideal gases each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume This trade-off of higher oxygen concentration for lower pressure is needed to maintain flexible spacesuits.
Scuba divers and submariners also rely on artificially-delivered O2, but most often use normal pressure, and/or mixtures of oxygen and air. Scuba diving is swimming underwater, or taking part in another activity while using a Scuba set. A submarine is a Watercraft that can operate independently below water as distinct from a Submersible that has only limited underwater capability Pure or nearly pure O2 use in diving at higher-than-sea-level pressures is usually limited to rebreather, decompression, or emergency treatment use at relatively shallow depths (~ 6 meters depth, or less). Deeper diving requires significant dilution of O2 with other gases, such as nitrogen or helium, to help prevent oxygen toxicity. Oxygen toxicity or oxygen toxicity syndrome (also known as the " Paul Bert effect" or the "Lorrain Smith effect" describes harmful effects caused
People who climb mountains or fly in non-pressurized fixed-wing aircraft sometimes have supplemental O2 supplies. Overview Fixed-wing aircraft range from small training and recreational aircraft to Wide-body aircraft and military cargo aircraft. [67] Passengers traveling in (pressurized) commercial airplanes have an emergency supply of O2 automatically supplied to them in case of cabin depressurization. Sudden cabin pressure loss activates chemical oxygen generators above each seat, causing oxygen masks to drop and forcing iron filings into the sodium chlorate inside the canister. A chemical oxygen generator is a device that releases Oxygen created by a Chemical reaction. An oxygen mask provides a method to transfer breathing Oxygen gas from a storage tank to the Lungs. Sodium chlorate ( Na[[Chlorine Cl]] O 3 is an Oxidizing agent. [38] A steady stream of oxygen gas is produced by the exothermic reaction. In Thermodynamics, the word exothermic "outside heating" describes a process or reaction that releases Energy usually in the form of Heat, but However, even this may pose a danger if inappropriately triggered: a ValuJet airplane crashed after use-date-expired O2 canisters, which were being shipped in the cargo hold, activated and caused fire. ValuJet Flight 592 was a flight that crashed on May 11 1996 en route from Miami International Airport in Miami Florida, United States to Hartsfield The canisters were mis-labeled as empty, and carried against dangerous goods regulations. A dangerous good is any Solid, Liquid, or Gas that can harm people other living Organisms property or the environment [68]
Oxygen, as a supposed mild euphoric, has a history of recreational use in oxygen bars and in sports. Euphoria is a medically recognized emotional state related to Pleasure and Happiness. The oxygen bar is a trend that started in the late 1990s in Japan and quickly spread east to California and Las Vegas Sport is an Activity that is governed by a set of rules or Customs and often engaged in competitively Oxygen bars are establishments, found in Japan, California, and Las Vegas, Nevada since the late 1990s that offer higher than normal O2 exposure for a fee. For a topic outline on this subject see List of basic Japan topics. California ( is a US state on the West Coast of the United States, along the Pacific Ocean. Las Vegas ( Spanish: "The Meadows" is the most populous City in the state of Nevada, the seat of Clark County, and an internationally [69] Professional athletes, especially in American football, also sometimes go off field between plays to wear oxygen masks in order to get a supposed "boost" in performance. American football, known in the United States and Canada simply as football, is a competitive Team sport known for mixing strategy with However, the reality of a pharmacological effect is doubtful; a placebo or psychological boost being the most plausible explanation. Placebo is a substance or procedure a patient accepts as medicine or therapy but which has no specific therapeutic activity [69] Available studies support a performance boost from enriched O2 mixtures only if they are breathed during actual aerobic exercise. [70] Other recreational uses include pyrotechnic applications, such as George Goble's five-second ignition of barbecue grills. The term "pyrotechnics" can also be used for Fireworks events This article is about the computer engineer For the late actor and comedian (1919-1991 whose name was spelled differently see George Gobel. barbeque block party Kansas cityjpg|thumb|right|275px|A barbecue on a trailer at a Block party in Kansas City. [71]
Industrial
Smelting of iron ore into steel consumes 55% of commercially-produced oxygen. Chemical reduction, or smelting, is a form of Extractive metallurgy. Iron ores are rocks and Minerals from which Metallic Iron can be economically extracted Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 [38] In this process, O2 is injected through a high-pressure lance into molten iron, which removes sulfur impurities and excess carbon as the respective oxides, SO2 and CO2. Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 The reactions are exothermic, so the temperature increases to 1700 °C. An exothermic reaction is a Chemical reaction that releases Heat. The Celsius Temperature scale was previously known as the centigrade scale. [38]
Another 25% of commercially-produced oxygen is used by the chemical industry. [38] Ethylene is reacted with O2 to create ethylene oxide, which, in turn, is converted into ethylene glycol; the primary feeder material used to manufacture a host of products, including antifreeze and polyester polymers (the precursors of many plastics and fabrics). Structure This Hydrocarbon has four Hydrogen Atoms bound to a pair of Carbon atoms that are connected by a Double bond. Ethylene glycol ( monoethylene glycol ( MEG) 12-ethanediol, IUPAC name: ethane-12-diol) is an Alcohol with two -OH Antifreeze is a Cryoprotectant used in Internal combustion engines and for many other heat transfer applications such as electronics cooling and Chillers Polyester is a category of Polymers which contain the Ester Functional group in their main chain Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products A textile is a flexible material comprised of a network of natural or artificial Fibres often referred to as thread or Yarn. [38]
Most of the remaining 20% of commercially-produced oxygen is used in medical applications, metal cutting and welding, as an oxidizer in rocket fuel, and in water treatment. Concerning a. " for the verdict on this matter --> Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding Rocket propellant is mass that is stored usually in some form of Propellant tank prior to being used as the propulsive mass that is ejected from a rocket engine in the form Water treatment describes those processes used to make water more acceptable for a desired end-use [38] Oxygen is used in oxyacetylene welding burning acetylene with O2 to produce a very hot flame. Concerning a. " for the verdict on this matter --> Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding Acetylene ( IUPAC name ethyne), C2H2 is a Hydrocarbon belonging to the group of Alkynes It is the simplest of all alkynes In this process, metal up to 60 cm thick is first heated with a small oxy-acetylene flame and then quickly cut by a large stream of O2. A centimetre ( American spelling: centimeter, symbol cm) is a unit of Length in the Metric system, equal to one hundredth [72] Rocket propulsion requires a fuel and an oxidizer. Spacecraft propulsion is any method used to change the velocity of Spacecraft and artificial Satellites There are many different methods Larger rockets use liquid oxygen as their oxidizer, which is mixed and ignited with the fuel for propulsion. A rocket or rocket vehicle is a Missile, Aircraft or other Vehicle which obtains Thrust by the reaction of the
Scientific
Paleoclimatologists measure the ratio of oxygen-18 and oxygen-16 in the shells and skeletons of marine organisms to determine what the climate was like millions of years ago (see oxygen isotope ratio cycle). Climate change is any long-term significant change in the “average weather” that a given region experiences Oxygen-18 ( 18O) is a natural stable Isotope of Oxygen and one of the Environmental isotopes. Paleoclimatology (also Palaeoclimatology) is the study of Climate change taken on the scale of the entire History of Earth. Oxygen-18 ( 18O) is a natural stable Isotope of Oxygen and one of the Environmental isotopes. In Biology, the skeleton is a strong and often a rigid framework that supports the body of an animal holding it upright and giving it shape and strength (Also skeletal Oxygen isotope ratio cycles are cyclical variations in the ratio of the mass of oxygen with an atomic weight of 18 to the mass of oxygen with an atomic weight of 16 present in Seawater molecules that contain the lighter isotope, oxygen-16, evaporate at a slightly faster rate than water molecules containing the 12% heavier oxygen-18; this disparity increases at lower temperatures. Seawater is Water from a Sea or Ocean. On average seawater in the world's oceans has a Salinity of about 3 Isotopes (Greek isos = "equal" tópos = "site place" are any of the different types of atoms ( Nuclides [73] During periods of lower global temperatures, snow and rain from that evaporated water tends to be higher in oxygen-16, and the seawater left behind tends to be higher in oxygen-18. Marine organisms then incorporate more oxygen-18 into their skeletons and shells than they would in a warmer climate. [73] Paleoclimatologists also directly measure this ratio in the water molecules of ice core samples that are up to several hundreds of thousands of years old. An ice core is a Core sample from the accumulation of snow and ice over many years that have re-crystallized and have trapped air bubbles from previous time periods
Planetary geologists have measured different abundances of oxygen isotopes in samples from the Earth, the Moon, Mars, and meteorites, but were long unable to obtain reference values for the isotope ratios in the Sun, believed to be the same as those of the primordial solar nebula. The geology of solar terrestrial planet mainly deals with the geological aspects of four planets of the Solar system namely Mercury, Venus, EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001 A meteorite is a natural object originating in Outer space that survives an impact with the Earth 's surface The Sun (Sol is the Star at the center of the Solar System. In Cosmogony, the nebular hypothesis is the most widely accepted model explaining the Formation and evolution of the Solar System. However, analysis of a silicon wafer exposed to the solar wind in space and returned by the crashed Genesis spacecraft has shown that the Sun has a higher proportion of oxygen-16 than does the Earth. Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14 The solar wind is a Stream of charged particles&mdasha plasma &mdashthat are ejected from the upper atmosphere of the Sun. The Genesis spacecraft was the first ever attempt to collect a sample of Solar wind, and the first " Sample return mission " to return from beyond the The measurement implies that an unknown process depleted oxygen-16 from the Sun's disk of protoplanetary material prior to the coalescence of dust grains that formed the Earth. A protoplanetary disk (or proplyd) is a rotating Circumstellar disk of dense gas surrounding a young newly formed star a T Tauri star or Herbig star [74]
Oxygen presents two spectrophotometric absorption bands peaking at the wavelengths 687 and 760 nm. An absorption band is a range of Wavelengths (or equivalently frequencies) in the Electromagnetic spectrum which are able to excite a particular A nanometre ( American spelling: nanometer, symbol nm) ( Greek: νάνος nanos dwarf; μετρώ metrό count) is a Some remote sensing scientists have proposed using the measurement of the radiance coming from vegetation canopies in those bands to characterize plant health status from a satellite platform. Remote sensing is the small or large-scale acquisition of information of an object or phenomenon by the use of either recording or real-time sensing device(s that is not in physical Earth observation satellites are Satellites specifically designed to observe Earth from Orbit, similar to Reconnaissance satellites but intended [75] This approach exploits the fact that in those bands it is possible to discriminate the vegetation's reflectance from its fluorescence, which is much weaker. In photometry and Heat transfer, reflectivity is the fraction of incident radiation reflected by a surface Fluorescence is a Luminescence that is mostly found as an The measurement is technically difficult owing to the low signal-to-noise ratio and the physical structure of vegetation; but it has been proposed as a possible method of monitoring the carbon cycle from satellites on a global scale. Signal-to-noise ratio (often abbreviated SNR or S/N) is an Electrical engineering concept also used in other fields (such as scientific Measurements The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the Biosphere, Pedosphere, Geosphere, Hydrosphere, and
Compounds
The oxidation state of oxygen is −2 in almost all known compounds of oxygen. In Chemistry, the oxidation state is an indicator of the degree of Oxidation of an Atom in a Chemical compound. The oxidation state −1 is found in a few compounds such as peroxides. A peroxide is a compound containing an Oxygen -oxygen single bond. [76] Compounds containing oxygen in other oxidation states are very uncommon: −1/2 (superoxides), −1/3 (ozonides), 0 (elemental, hypofluorous acid), +1/2 (dioxygenyl), +1 (dioxygen difluoride), and +2 (oxygen difluoride). Superoxide is the Anion O2&minus It is important as the product of the one-electron reduction of Dioxygen, which occurs widely in nature Ozonide is an unstable reactive polyatomic Anion O3&minus derived from Ozone, or an organic compound similar to Organic peroxide There are several known Allotropes of oxygen Dioxygen, O2 - colorless Ozone, O3 - blue Tetraoxygen Hypofluorous acid is the Chemical compound with the formula HOF The dioxygenyl Ion, O2+ is a rarely-encountered Oxycation in which both Oxygen Atoms have an Oxidation state Dioxygen difluoride is a compound with the formula O2F2 This yellow compound is a strong oxidant and decomposes into OF2 and oxygen Oxygen difluoride is the Chemical compound with the formula OF2
Oxides and other inorganic compounds
Water (H2O) is the oxide of hydrogen and the most familiar oxygen compound. Water is a common Chemical substance that is essential for the survival of all known forms of Life. An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Hydrogen atoms are covalently bonded to oxygen in a water molecule but also have an additional attraction (about 23. 3 kJ·mol−1 per hydrogen atom) to an adjacent oxygen atom in a separate molecule. [77] These hydrogen bonds between water molecules hold them approximately 15% closer than what would be expected in a simple liquid with just Van der Waals forces. A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen The Van der Waals equation is an Equation of state that can be derived from a special form of the potential between a pair of molecules (hard-sphere repulsion [78][79]
Due to its electronegativity, oxygen forms chemical bonds with almost all other elements at elevated temperatures to give corresponding oxides. " Electronegativity " is the opposite of " Electropositivity," which describes an element's ability to donate electrons A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element However, some elements readily form oxides at standard conditions for temperature and pressure; the rusting of iron is an example. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made Rust is a general term for a series of Iron oxides, usually red oxides formed by the reaction of Iron with Oxygen in the presence of water or air Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 The surface of metals like aluminium and titanium are oxidized in the presence of air and become coated with a thin film of oxide that passivates the metal and slows further corrosion. WikipediaNaming Titanium (taɪˈteɪniəm is a Chemical element with the symbol Ti and Atomic number 22 Passivation is the process of making a material "passive" in relation to another material prior to using the materials together Corrosion means the breaking down of essential properties in a material due to Chemical reactions with its surroundings Some of the transition metal oxides are found in nature as non-stoichiometric compounds, with a slightly less metal than the chemical formula would show. Non-stoichiometric compounds are Chemical compounds with an elemental composition that cannot be represented by a ratio of well-defined Natural numbers and A chemical formula is a way of expressing information about the Atoms that constitute a particular Chemical compound, and how the relationship between those atoms changes For example, the natural occurring FeO (wüstite) is actually written as Fe1−xO, where x is usually around 0. Iron(II oxide, also known as ferrous oxide, iron oxide/oxidized iron or more commonly rusted Wüstite ( Fe[[oxygen O]] is a mineral form of Iron(II oxide found with Meteorites and native Iron. 05. [80]
Oxygen as a compound is present in the atmosphere in trace quantities in the form of carbon dioxide (CO2). Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single The earth's crustal rock is composed in large part of oxides of silicon (silica SiO2, found in granite and sand), aluminium (aluminium oxide Al2O3, in bauxite and corundum), iron (iron(III) oxide Fe2O3, in hematite and rust) and other metals. In Geology, a crust is the outermost solid shell of a planet or moon In Geology, rock is a naturally occurring aggregate of Minerals and/or Mineraloids The Earth's outer solid layer the ‘ Lithosphere Silicon (ˈsɪlɪkən or /ˈsɪlɪkɒn/ silicium is the Chemical element that has the symbol Si and Atomic number 14 The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide Granite (ˈɡrænɪt is a common and widely occurring type of intrusive, Felsic, igneous rock. Sand is a naturally occurring Granular material composed of finely divided rock and Mineral particles WikipediaNaming Bauxite is the most important Aluminium Ore. It consists largely of the minerals Gibbsite Al(OH3 Boehmite γ-AlO(OH and Corundum (from Tamil kurundam குருந்தம் or kuruvindam குருவிந்தம் is a Crystalline form of Iron(III oxide —also known as ferric oxide, Hematite, red iron oxide, synthetic maghemite, colcothar, or simply Rust —is Hematite, also spelt hæmatite, is the Mineral form of Iron(III oxide (Fe2O3 one of several Iron oxides Rust is a general term for a series of Iron oxides, usually red oxides formed by the reaction of Iron with Oxygen in the presence of water or air The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across
The rest of the Earth's crust is also made of oxygen compounds, in particular calcium carbonate (in limestone) and silicates (in feldspars). Calcium carbonate is a Chemical compound with the Chemical formula Ca[[Carbon C]] O 3 Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 For the Artificial intelligence Androids of the 1990s Science fiction series Space Above and Beyond, see Silicate (AI Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. Water-soluble silicates in the form of Na4SiO4, Na2SiO3, and Na2Si2O5 are used as detergents and adhesives. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. A detergent (as a noun is a material intended to assist Cleaning. Glue or adhesive is a compound that adheres or bonds two items together [81]
Oxygen also acts as a ligand for transition metals, forming metal–O2 bonds with the iridium atom in Vaska's complex,[82] with the platinum in PtF6,[83] and with the iron center of the heme group of hemoglobin. Iridium (ɪˈrɪdiəm is a Chemical element that has the symbol Ir and Atomic number 77 Vaska's complex is the Trivial name for the Chemical compound trans -chlorocarbonylbis(triphenylphosphineiridium(I which has the formula IrCl(CO2 Platinum (ˈplætɪnəm is a Chemical element with the Atomic symbol Pt and an Atomic number of 78 Platinum hexafluoride is the Chemical compound with the formula Pt[[Fluorine F6]] A heme ( American English) or haem ( British English) is a Prosthetic group that consists of an Iron atom contained in the center of Hemoglobin ( also spelled haemoglobin and abbreviated Hb or Hgb) is the Iron -containing Oxygen -transport Metalloprotein
Organic compounds and biomolecules
(oxygen is in red, carbon in black and hydrogen in white). Acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and β-ketopropane) is a colorless mobile flammable
Among the most important classes of organic compounds that contain oxygen are (where "R" is an organic group): alcohols (R-OH); ethers (R-O-R); ketones (R-CO-R); aldehydes (R-CO-H); carboxylic acids (R-COOH); esters (R-COO-R); acid anhydrides (R-CO-O-CO-R); and amides (R-C(O)-NR2). In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon Ether is a class of Organic compounds which contain an ether group — an Oxygen Atom connected to two (substituted Alkyl A ketone (pronounced as key tone) is either the Functional group characterized by a Carbonyl group (O=C linked to two other Carbon atoms or An aldehyde is an organic compound containing a terminal Carbonyl group. Carboxylic acids are Organic acids characterized by the presence of a Carboxyl group, which has the formula -C(=OOH usually written -COOH or -CO2H Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least An acid anhydride is an Organic compound that has two Acyl groups bound to the same Oxygen atom In Chemistry, an amide is one of three kinds of Compounds (sometimes called acid amide the organic Functional group characterized There are many important organic solvents that contain oxygen, including: acetone, methanol, ethanol, isopropanol, furan, THF, diethyl ether, dioxane, ethyl acetate, DMF, DMSO, acetic acid, and formic acid. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and β-ketopropane) is a colorless mobile flammable Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naphtha or wood spirits, is a Chemical compound Isopropyl alcohol (also isopropanol, iso, isopro, Rubbing alcohol, or the abbreviation IPA) is a common name for Furan, also known as furane and furfuran, is a heterocyclic Organic compound. "THF" redirects here For other uses see THF (disambiguation. Diethyl ether, also known as ether and ethoxyethane, is a clear colorless and highly Flammable liquid with a low Boiling point and a Ethyl acetate ( systematically, ethyl ethanoate commonly abbreviated EtOAc or EA is the Organic compound with the formula CH3COOCH2CH3 Dimethylformamide is the Organic compound with the formula ( CH3)2NC(OH Dimethyl sulfoxide (DMSO is the Chemical compound with the formula (CH32SO Acetic acid, also known as ethanoic acid, is an organic chemical compound, giving Vinegar its sour taste Formic acid (systematically called methanoic acid) is the simplest Carboxylic acid. Acetone ((CH3)2CO) and phenol (C6H5OH) are used as feeder materials in the synthesis of many different substances. Acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and β-ketopropane) is a colorless mobile flammable Phenol, is a toxic colourless Crystalline Solid with a sweet tarry odor commonly referred to as a "hospital smell" Other important organic compounds that contain oxygen are: glycerol, formaldehyde, glutaraldehyde, citric acid, acetic anhydride, and acetamide. Formaldehyde is a Chemical compound with the formula H2CO It is the simplest Aldehyde —an organic compound containing a terminal Carbonyl Glutaraldehyde is a colorless liquid with a pungent odor used to sterilize medical and dental equipment Citric acid is a weak organic Acid. It is a natural Preservative and is also used to add an acidic or sour taste to foods and Soft drinks Acetic anhydride is the Chemical compound with the formula (CH3CO2O Acetamide (or acetic acid amide or ethanamide) CH3CONH2 the Amide of Acetic acid, is a white crystalline solid in Epoxides are ethers in which the oxygen atom is part of a ring of three atoms. An epoxide is a cyclic Ether with only three ring atoms This ring approximately is an Equilateral triangle, i Ether is a class of Organic compounds which contain an ether group — an Oxygen Atom connected to two (substituted Alkyl
Oxygen reacts spontaneously with many organic compounds at or below room temperature in a process called autoxidation. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation Autoxidation is any Oxidation that occurs in open air or in presence of Oxygen and/or UV radiation and forms Peroxides and Hydroperoxides [84] Most of the organic compounds that contain oxygen are not made by direct action of O2. An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. Organic compounds important in industry and commerce that are made by direct oxidation of a precursor include ethylene oxide and peracetic acid. Peracetic acid ( peroxyacetic acid, or PAA) is a Chemical in the Organic peroxide family [81]
The element is found in almost all biomolecules that are important to (or generated by) life. A biomolecule is any organic Molecule that is produced by living Organisms including large Polymeric molecules such as Proteins Only a few common complex biomolecules, such as squalene and the carotenes, contain no oxygen. Squalene is a natural Organic compound originally obtained for commercial purposes primarily from Shark liver oil, though there are botanic sources as well including The term carotene is used for several related substances having the formula C40H56 Of the organic compounds with biological relevance, carbohydrates contain the largest proportion by mass of oxygen. Carbohydrates (from ' Hydrates of Carbon ' or saccharides ( Greek σάκχαρον meaning " Sugar " are the most All fats, fatty acids, amino acids, and proteins contain oxygen (due to the presence of carbonyl groups in these acids and their ester residues). Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water In Chemistry, especially Biochemistry, a fatty acid is a Carboxylic acid often with a long unbranched Aliphatic tail ( chain) which In Chemistry, an amino acid is a Molecule containing both Amine and Carboxyl Functional groups In Biochemistry, this Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least Oxygen also occurs in phosphate (PO43−) groups in the biologically important energy-carrying molecules ATP and ADP, in the backbone and the purines (except adenine) and pyrimidines of RNA and DNA, and in bones as calcium phosphate and hydroxylapatite. A phosphate, an Inorganic chemical, is a salt of Phosphoric acid. Adenosine-5'-triphosphate ( ATP) is a multifunctional Nucleotide that is most important as a " molecular currency" of intracellular Energy Adenosine diphosphate, abbreviated ADP, is a Nucleotide. It is an Ester of Pyrophosphoric acid with the Nucleoside Adenosine Purine ( 1) is a heterocyclic Aromatic Organic compound, consisting of a Pyrimidine ring fused to an Imidazole ring Adenine is a Purine with a variety of roles in Biochemistry including Cellular respiration, in the form of both the energy-rich Adenosine Pyrimidine is a Heterocyclic Aromatic Organic compound similar to Benzene and Pyridine, containing two Nitrogen Atoms Ribonucleic acid ( RNA) is a Nucleic acid that consists of a long chain of Nucleotide units Deoxyribonucleic acid ( DNA) is a Nucleic acid that contains the genetic instructions used in the development and functioning of all known Calcium phosphate is the name given to a family of Minerals containing Calcium Ions (Ca2+ together with orthophosphates (PO43- Hydroxylapatite, also called hydroxyapatite, is a Mineral. It is a naturally occurring form of calcium Apatite with the formula Ca5(PO43(OH
Precautions
Toxicity
Oxygen gas (O2) can be toxic at elevated partial pressures, leading to convulsions and other health problems. Oxygen toxicity or oxygen toxicity syndrome (also known as the " Paul Bert effect" or the "Lorrain Smith effect" describes harmful effects caused Oxygen toxicity or oxygen toxicity syndrome (also known as the " Paul Bert effect" or the "Lorrain Smith effect" describes harmful effects caused In a mixture of Ideal gases each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume An epileptic seizure is caused by excessive and/or hypersynchronous electrical Neuronal activity and is usually self-limiting [85][86] Oxygen toxicity usually begins to occur at partial pressures more than 50 kilopascals (kPa), or 2. 5 times the normal sea-level O2 partial pressure of about 21 kPa. Therefore, air supplied through oxygen masks in medical applications is typically composed of 30% O2 by volume (about 30 kPa at standard pressure). An oxygen mask provides a method to transfer breathing Oxygen gas from a storage tank to the Lungs. [25] At one time, premature babies were placed in incubators containing O2-rich air, but this practice was discontinued after some babies were blinded by it. Premature birth (also known as preterm birth) is the Birth of a Baby before the standard period of Pregnancy is completed [25]
Breathing pure O2 in space applications, such as in some modern space suits, or in early spacecraft such as Apollo, causes no damage due to the low total pressures used. A space suit is a complex system of Garments equipment and environmental systems designed to keep a person alive and comfortable in the harsh environment of outer space [87] In the case of spacesuits, the O2 partial pressure in the breathing gas is, in general, about 30 kPa (1. 4 times normal), and the resulting O2 partial pressure in the astronaut's arterial blood is only marginally more than normal sea-level O2 partial pressure (see arterial blood gas). An arterial blood gas ( ABG) is a Blood test that is performed specifically on Blood from an Artery.
Oxygen toxicity to the lungs and central nervous system can also occur in deep scuba diving and surface supplied diving. In Vertebrates the central nervous system ( CNS) is the part of the Nervous system which is enclosed in the Meninges. Scuba diving is swimming underwater, or taking part in another activity while using a Scuba set. Surface supplied diving (also known as Hooka diving refers to divers using equipment supplied with Breathing gas using an umbilical cord [25] Prolonged breathing of an air mixture with an O2 partial pressure more than 60 kPa can eventually lead to permanent pulmonary fibrosis. Idiopathic pulmonary fibrosis (IPF, also known as cryptogenic fibrosing alveolitis, is a Chronic, progressive interstitial lung disease with an unknown [88] Exposure to a O2 partial pressures greater than 160 kPa may lead to convulsions (normally fatal for divers). Acute oxygen toxicity can occur by breathing an air mixture with 21% O2 at 66 m or more of depth while the same thing can occur by breathing 100% O2 at only 6 m. [88][89]
Combustion and other hazards
Highly-concentrated sources of oxygen promote rapid combustion. Combustion or burning is a complex sequence of Exothermic chemical reactions between a Fuel and an Oxidant accompanied by the production of Fire and explosion hazards exist when concentrated oxidants and fuels are brought into close proximity; however, an ignition event, such as heat or a spark, is needed to trigger combustion. Fire is the heat and light energy released during a Chemical reaction, in particular a combustion reaction. An explosion is a sudden increase in Volume and release of Energy in an extreme manner usually with the generation of high Temperatures and the release Fuel is any material that is burned or altered in order to obtain energy [90] Oxygen itself is not the fuel, but the oxidant. Combustion hazards also apply to compounds of oxygen with a high oxidative potential, such as peroxides, chlorates, nitrates, perchlorates, and dichromates because they can donate oxygen to a fire. A peroxide is a compound containing an Oxygen -oxygen single bond. The chlorate anion has the formula ClO3− In this case the Chlorine atom is in the +5 Oxidation state. In Inorganic chemistry, a nitrate is a salt of Nitric acid with an Ion composed of one Nitrogen and three Oxygen atoms Perchlorates are the salts derived from Perchloric acid ( H[[chlorine Cl]] O4) Chromates and dichromates are Salts of Chromic acid and dichromic acid respectively
Concentrated O2 will allow combustion to proceed rapidly and energetically. [90] Steel pipes and storage vessels used to store and transmit both gaseous and liquid oxygen will act as a fuel; and therefore the design and manufacture of O2 systems requires special training to ensure that ignition sources are minimized. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 [90] The fire that killed the Apollo 1 crew on a test launch pad spread so rapidly because the capsule was pressurized with pure O2 but at slightly more than atmospheric pressure, instead of the ⅓ normal pressure that would be used in a mission. [91][92]
Liquid oxygen spills, if allowed to soak into organic matter, such as wood, petrochemicals, and asphalt can cause these materials to detonate unpredictably on subsequent mechanical impact. Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs Petrochemicals are chemical products made from raw materials of Petroleum or other Hydrocarbon origin Asphalt ( is a sticky black and highly viscous liquid or semi-solid that is present in most crude Petroleums and in some natural deposits sometimes termed asphaltum Detonation is a process of Supersonic Combustion in which a Shock wave is propagated forward due to energy release in a reaction zone behind it [90] On contact with the human body, it can also cause cryogenic burns to the skin and the eyes. Cryogenics is often used incorrectly to refer to Cryonics, cryopreserving humans or animals
See also
- Oxygen compounds
- Hypoxia, a lack of oxygen
- Hypoxia (environmental) for O2 depletion in aquatic ecology
- Winkler test for dissolved oxygen for instructions on how to determine the amount of O2 dissolved in fresh water. Chronic Hypoxia is a pathological condition in which the body as a whole ( generalized hypoxia) or region of the body ( tissue hypoxia) is deprived of adequate For other uses of the term "hypoxia" see Hypoxia. Hypoxia or oxygen depletion is a phenomenon that occurs in aquatic environments The Winkler test is used to determine the level of dissolved Oxygen in water samples
- Optode for a method of measuring O2 concentration in solution
- Oxygen Catastrophe in geology
- Oxygen isotope ratio cycle
Notes and citations
- ^ a b Emsley 2001, p. An optode or optrode is an optical Sensor device that optically measures a specific substance usually with the aid of a chemical Transducer. The Oxygen Catastrophe was a massive environmental change believed to have happened during the Siderian period at the beginning of the Paleoproterozoic Oxygen isotope ratio cycles are cyclical variations in the ratio of the mass of oxygen with an atomic weight of 18 to the mass of oxygen with an atomic weight of 16 present in 297
- ^ a b Oxygen. Los Alamos National Laboratory. Retrieved on 2007-12-16. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 755 - An Lushan revolts against Chancellor Yang Guozhong at Fanyang, initiating the An Shi Rebellion
- ^ a b c d e f g h i j Cook & Lauer 1968, p. 500
- ^ NASA (2007-09-27). The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space program Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 489 - Odoacer attacks Theodoric at the Battle of Verona and is defeated again "NASA Research Indicates Oxygen on Earth 2.5 Billion Years Ago". Press release. A news release, media release, press release or press statement is a written or recorded Communication directed at members of the News Retrieved on 2008-03-13. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1138 - Cardinal Gregorio Conti is elected Antipope as Victor IV, succeeding Anacletus II.
- ^ a b c d Mellor 1939
- ^ Molecular Orbital Theory. Purdue University. Retrieved on 2008-01-28. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1077 - Walk to Canossa: The Excommunication of Henry IV Holy Roman Emperor is lifted
- ^ Pauling, L. The Nature of the Chemical Bond. Cornell University Press, 1960.
- ^ a b Jakubowski, Henry. Biochemistry Online. Saint John's University. Retrieved on 2008-01-28. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1077 - Walk to Canossa: The Excommunication of Henry IV Holy Roman Emperor is lifted
- ^ An orbital is a concept from quantum mechanics that models an electron as a wave-like particle that has a spacial distribution about an atom or molecule. Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons In Physics and Chemistry, wave–particle duality is the concept that all Matter and Energy exhibits both Wave -like and
- ^ a b c Emsley 2001, p. 303
- ^ Demonstration of a bridge of liquid oxygen supported against its own weight between the poles of a powerful magnet. University of Wisconsin-Madison Chemistry Department DEMONSTRATION LAB. Retrieved on 2007-12-15. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 533 - Byzantine general Belisarius defeats the Vandals, commanded by King Gelimer, at the Battle of
- ^ Oxygen's paramagnetism can be used analytically in paramagnetic oxygen gas analysers that determine the purity of gaseous oxygen. (Company literature of Oxygen analyzers (triplet). Servomex. Retrieved on 2007-12-15. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 533 - Byzantine general Belisarius defeats the Vandals, commanded by King Gelimer, at the Battle of )
- ^ Krieger-Liszkay 2005, 337-46
- ^ Harrison 1990
- ^ Wentworth 2002
- ^ Hirayama 1994, 149-150
- ^ Chieh, Chung. Bond Lengths and Energies. University of Waterloo. Retrieved on 2007-12-16. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 755 - An Lushan revolts against Chancellor Yang Guozhong at Fanyang, initiating the An Shi Rebellion
- ^ a b Stwertka 1998, p. 48
- ^ Stwertka 1998, p. 49
- ^ a b Cacace 2001, 4062
- ^ a b Ball, Phillip. "New form of oxygen found", Nature News, 2001-09-16. Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar. Events 1400 - Owain Glyndŵr is declared Prince of Wales by his followers Retrieved on 2008-01-09. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 475 - Byzantine Emperor Zeno is forced to flee his capital at Constantinople.
- ^ Lundegaard 2006, 201–04
- ^ Desgreniers 1990, 1117–22
- ^ Shimizu 1998, 767–69
- ^ a b c d e f Emsley 2001, p. 299
- ^ Air solubility in water. The Engineering Toolbox. Retrieved on 2007-12-21. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 69 - The end of the Year of the four emperors: Following Galba, Otho and Vitellius, Vespasian
- ^ Evans & Claiborne 2006, 88
- ^ Lide 2003, Section 4
- ^ Overview of Cryogenic Air Separation and Liquefier Systems. Universal Industrial Gases, Inc. . Retrieved on 2007-12-15. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 533 - Byzantine general Belisarius defeats the Vandals, commanded by King Gelimer, at the Battle of
- ^ Liquid Oxygen Material Safety Data Sheet (PDF). Matheson Tri Gas. Retrieved on 2007-12-15. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 533 - Byzantine general Belisarius defeats the Vandals, commanded by King Gelimer, at the Battle of
- ^ a b c d e Oxygen Nuclides / Isotopes. EnvironmentalChemistry. com. Retrieved on 2007-12-17. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 546 - Gothic War (535–554: The Ostrogoths of King Totila
- ^ a b c Meyer 2005, 9022
- ^ a b c d Emsley 2001, p. 298
- ^ Figures given are for values up to 50 miles (80 km) above the surface
- ^ Walker 1980
- ^ This is calculated by dividing all the free O2 in the atmosphere to the rate it is used for respiration by the entire biosphere. This is obviously an extreme calculation since most organisms would die well before the pressure of O2 fell to zero, and therefore the rate of consumption would decrease significantly from the present rate.
- ^ From The Chemistry and Fertility of Sea Waters by H. W. Harvey, 1955, citing C. J. J. Fox, "On the coefficients of absorption of atmospheric gases in sea water", Publ. Circ. Cons. Explor. Mer, no. 41, 1907. Harvey however notes that according to later articles in Nature the values appear to be about 3% too high.
- ^ a b c d e f g h Emsley 2001, p. 301
- ^ Fenical 1983, "Marine Plants"
- ^ Brown 2003, 958
- ^ Thylakoid membranes are part of chloroplasts in algae and plants while they simply are one of many membrane structures in cyanobacteria. Chloroplasts are Organelles found in Plant cells and eukaryotic Algae that conduct Photosynthesis. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy In fact, chloroplasts are thought to have evolved from cyanobacteria that were once symbiotic partners with the progenerators of plants and algae. Cyanobacteria, also known as blue-green algae, blue-green bacteria or Cyanophyta, is a phylum of Bacteria that obtain their energy
- ^ a b Raven 2005, 115–27
- ^ Water oxidation is catalyzed by a manganese-containing enzyme complex known as the oxygen evolving complex (OEC) or water-splitting complex found associated with the lumenal side of thylakoid membranes. Manganese (ˈmæŋgəniːz is a Chemical element, designated by the symbol Mn. Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins The oxygen evolving complex, (OEC also known as the water-splitting complex is a water oxidizing enzyme involved in the photooxidation of water during the Light reactions Manganese is an important cofactor, and calcium and chloride are also required for the reaction to occur. A cofactor is a non-protein Chemical compound that is bound (either tightly or loosely to an Enzyme and is required for Catalysis. Calcium (ˈkælsiəm is the Chemical element with the symbol Ca and Atomic number 20 The chloride Ion is formed when the element Chlorine picks up one Electron to form an Anion (negatively-charged ion Cl&minus (Raven 2005)
- ^ CO2 is released from another part of hemoglobin (see Bohr effect)
- ^ "For humans, the normal volume is 6-8 liters per minute. Bohr effect is a property of Hemoglobin first described in 1904 by the Danish physiologist Christian Bohr (father of physicist Niels Bohr) which states " [1]
- ^ (1. 8 grams)*(60 minutes)*(24 hours)*(365 days)*(6. 6 billion people)/1,000,000=6. 24 billion tonnes
- ^ Campbell 2005, 522–23
- ^ Freeman 2005, 214, 586
- ^ a b Berner 1999, 10955–57
- ^ Dole 1965, 5–27
- ^ Jastrow 1936, 171
- ^ a b c d e Cook & Lauer 1968, p. 499.
- ^ a b c Britannica contributors 1911, "John Mayow"
- ^ a b World of Chemistry contributors 2005, "John Mayow"
- ^ Morris 2003
- ^ a b c d e f g h Emsley 2001, p. 300
- ^ Priestley 1775, 384–94
- ^ DeTurck, Dennis; Gladney, Larry and Pietrovito, Anthony (1997). The Interactive Textbook of PFP96. University of Pennsylvania. Retrieved on 2008-01-28. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1077 - Walk to Canossa: The Excommunication of Henry IV Holy Roman Emperor is lifted
- ^ Roscoe 1883, 38
- ^ However, these results were mostly ignored until 1860. Part of this rejection was due to the belief that atoms of one element would have no chemical affinity towards atoms of the same element, and part was due to apparent exceptions to Avogadro's law that were not explained until later in terms of dissociating molecules. In Chemical physics and Physical chemistry, chemical affinity can be defined as electronic properties by which dissimilar Chemical species are capable of
- ^ a b Daintith 1994, p. 707
- ^ a b c How Products are Made contributors, "Oxygen"
- ^ Goddard-1926. NASA. Retrieved on 2007-11-18. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 326 - The old St Peter's Basilica is consecrated 1302 - Pope Boniface VIII issues the Papal bull
- ^ Non-Cryogenic Air Separation Processes. UIG Inc. (2003). Retrieved on 2007-12-16. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 755 - An Lushan revolts against Chancellor Yang Guozhong at Fanyang, initiating the An Shi Rebellion
- ^ Space Shuttle Use of Propellants and Fluids, National Aeronautics and Space Administration, 2001=09, <http://www-pao.ksc.nasa.gov/kscpao/nasafact/ps/SSP.ps>. Retrieved on 16 December 2007
- ^ a b Cook & Lauer 1968, p. 510
- ^ The reason is that increasing the proportion of oxygen in the breathing gas at low pressure acts to augment the inspired O2 partial pressure nearer to that found at sea-level. In a mixture of Ideal gases each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume
- ^ NTSB Summary report. National Transportation Safety Board. Retrieved on 2007-12-16. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 755 - An Lushan revolts against Chancellor Yang Guozhong at Fanyang, initiating the An Shi Rebellion )
- ^ a b Bren, Linda (November–December 2002). Oxygen Bars: Is a Breath of Fresh Air Worth It?. FDA Consumer magazine. U. S. Food and Drug Administration. Retrieved on 2007-12-23. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 962 - Byzantine-Arab Wars: Under the future Emperor Nicephorus Phocas, Byzantine troops stormed the city
- ^ Ergogenic Aids. Peak Performance Online. Retrieved on 2008-01-04. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 46 BC - Titus Labienus defeats Julius Caesar in the Battle of Ruspina.
- ^ George Goble's extended home page (mirror).
- ^ Cook & Lauer 1968, p. 508
- ^ a b Emsley 2001, p. 304
- ^ Hand, Eric (2008-03-13). "The Solar System's first breath". Nature 452: 259. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
- ^ Miller et al. 2003
- ^ Greenwood & Earnshaw 1997, 28
- ^ Maksyutenko et al. 2006
- ^ Chaplin, Martin (2008-01-04). 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 46 BC - Titus Labienus defeats Julius Caesar in the Battle of Ruspina. Water Hydrogen Bonding. Retrieved on 2008-01-06. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1066 - Harold Godwinson is crowned King of England. 1205 - Philip of Swabia becomes King
- ^ Also, since oxygen has a higher electronegativity than hydrogen, the charge difference makes it a polar molecule. "Polar molecule" and "Non-polar" redirect here The interactions between the different dipoles of each molecule cause a net attraction force. In physics there are two kinds of dipoles ( Hellènic: di(s- = two- and pòla = pivot hinge An electric dipole is a
- ^ Smart 2005, 214
- ^ a b Cook & Lauer 1968, p. 507
- ^ Crabtree 2001, 152
- ^ Cook & Lauer 1968, p. 505
- ^ Cook & Lauer 1968, p. 506
- ^ Since O2's partial pressure is the fraction of O2 times the total pressure, elevated partial pressures can occur either from high O2 fraction in breathing gas or from high breathing gas pressure, or a combination of both.
- ^ Cook & Lauer 1968, p. 511
- ^ Wade, Mark (2007). Space Suits. Encyclopedia Astronautica. Retrieved on 2007-12-16. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 755 - An Lushan revolts against Chancellor Yang Guozhong at Fanyang, initiating the An Shi Rebellion
- ^ a b Wilmshurst, Peter (1998). ABC of oxygen: Diving and oxygen. British Medical Journal. Retrieved on 2008-01-06. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Events 1066 - Harold Godwinson is crowned King of England. 1205 - Philip of Swabia becomes King
- ^ Donald 1992
- ^ a b c d Werley 1991
- ^ No single ignition source of the fire was conclusively identified, although some evidence points to arc from an electrical spark). (Report of Apollo 204 Review Board NASA Historical Reference Collection, NASA History Office, NASA HQ, Washington, DC)
- ^ Chiles 2001
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External links
- Los Alamos National Laboratory – Oxygen
- WebElements.com – Oxygen
- Oxygen (O2) Properties, Uses, Applications
- Oxidizing Agents > Oxygen
- Roald Hoffmann article on "The Story of O"
Dictionary
oxygen
-noun
- A chemical element (symbol O) with an atomic number of 8 and relative atomic mass of 15.9994.
- Molecular oxygen (O2), a colorless, odorless gas at room temperature.
- (medicine) A mixture of oxygen and other gases, administered to a patient to help him or her to breathe.
- (countable) An atom of this element.
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