Definition
Oxygen is a chemical element; it has the symbol O and its atomic number is 8. It is a member of the chalcogen group in the periodic table. It is highly reactive, a nonmetal, and a potent oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is the most abundant element in Earth's crust, making up almost half of the Earth's crust in the form of various oxides such as water, carbon dioxide, iron oxides, and silicates. It is also the third-most abundant element in the universe after hydrogen and helium.
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1,4-DioxaneASTM InternationalAbsorption bandAbundance of chemical elementsAbundance of elements in Earth's crustAcetamideAcetic acidAcetic anhydrideAcetoneAcetyleneAcidActiniumAdenosine triphosphateAdhesiveAerobic exerciseAerobic respirationAir pollutantAir pollutionAir separationAirglowAlcohol (chemistry)AldehydeAlexander von HumboldtAlkali metalAlkaline earth metalAllotropes of oxygenAllotropyAluminiumAluminium oxideAmbient pressureAmedeo AvogadroAmerican footballAmericiumAmericium(III) oxideAmericium dioxideAmideAnaerobic bacteriaAnaerobic organismAncient GreekAntibondingAntifreezeAntimonyAntoine LavoisierApollo 1Apollo spacecraftAquatic animalArgonArsenicArsenic pentoxideArsenic trioxideArterial systemArthropodAstatineAstrobiologyAstrochemistryAtmosphere (unit)Atmosphere of EarthAtmospheric diving suitsAtomic massAtomic numberAtomic orbitalAuburn, MassachusettsAufbau principleAuroraAutotrophAutoxidationAvogadro's lawBBCBarbecueBariumBarium oxideBauxiteBerkeliumBerylliumBeryllium oxideBeta decayBeta plus decayBiochemical oxygen demandBiodiverseBiogeochemical cycleBiomoleculeBiosignatureBiosphereBismuthBismuth(III) oxideBismuth pentoxideBismuth tetroxideBitumenBlock (periodic table)Bohr effectBohriumBoiling pointBond orderBoronBoron groupBoron trioxideBreathingBreathing gasBrin processBromineBromine dioxideByproductCAS Registry NumberCNO cycleCRC PressCadmiumCadmium oxideCaesiumCaesium sesquioxideCalciumCalcium carbonateCalcium oxideCalcium peroxideCaliforniumCalvin cycleCalxCarbohydrateCarbonCarbon cycleCarbon dioxideCarbon groupCarbon monoxideCarbon monoxide poisoningCarbon suboxideCarboxylic acidCarl Wilhelm ScheeleCarl ZimmerCarl von LindeCarotenoidCascade (chemical engineering)Celestial bodiesCellular respirationCelsiusCentral nervous systemCeramicCeriumCerium(III) oxideCerium(III,IV) oxideCerium(IV) oxideCesium superoxideChalcogenCharles DarwinChemical bondChemical compoundChemical elementChemical energyChemical formulaChemical oxygen generatorChemical symbolChlorideChlorineChlorine dioxideChlorine perchlorateChlorine peroxideChlorophyllChloroplastChromic chromateChromiumChromium(III) oxideChromium(IV) oxideChromium trioxideCirculatory systemCitric acidCladeClimate variability and changeCluster chemistryCobaltCobalt(II) oxideCobalt(II,III) oxideCobalt(III) oxideCofactor (biochemistry)CombustionCommission on Isotopic Abundances and Atomic WeightsCongestive heart failureConvulsionCoperniciumCopperCopper(II) oxideCorrosionCorrosion in spaceCorrosiveCorundumCosmochemistryCovalent bondCovalent bondingCovalent radiusCritical point (thermodynamics)Crust (geology)CryogenicsCrystal structureCubic crystal systemCuriumCutaneous respirationCyanobacteriaD-blockDark oxygenDarmstadtiumDecarburizationDecay modeDecay productDecompositionDecompression (diving)Decompression sicknessDegenerate orbitalsDensityDetergentDetonationDiargonDiatomicDiatomic carbonDiatomic moleculeDibromine pentoxideDibromine trioxideDichlorine heptoxideDichlorine hexoxideDichlorine monoxideDichlorine trioxideDiethyl etherDiffuse sky radiationDiffusionDilithiumDimethyl sulfoxideDimethylformamideDinitrogen pentoxideDinitrogen tetroxideDioxygenDioxygen difluorideDioxygen in biological reactionsDioxygen monofluorideDioxygenylDioxygenyl hexafluoroplatinateDiphosphorusDipoleDirubidiumDiseaseDissolved oxygenDistillationDisulfurDouble bondDubniumDynamic viscosityDysprosiumDysprosium(III) oxideEarthEarth's atmosphereEarth's crustEarth's historyEarth observation satelliteEinsteiniumElectrolysis of waterElectromagnetic spectrumElectron configurationElectronegativityEmphysemaEncyclopædia Britannica Eleventh EditionEnteral respirationEnthalpy of fusionEnthalpy of vaporizationEnzymeEpoxideErasmus DarwinErbiumErbium(III) oxideEsterEthanolEtherEthyl acetateEthyleneEthylene glycolEthylene oxideEukaryoteEukaryoticEuphoriaEuropa (moon)EuropiumEuropium(III) oxideEvaporationEvolution of lifeEvolutionary history of lifeExchange energyExhaust systemExoplanetExoskeletonExothermicExothermic reactionExperiments and Observations on Different Kinds of AirExtraterrestrial atmosphereExtraterrestrial lifeF-blockFabricFatFermiumFire (classical element)Fixed-wing aircraftFleroviumFluorescenceFluorineFormaldehydeFormic acidFoundations of ChemistryFractional distillationFranciumFree oxygenFrench Academy of SciencesFuranGHS hazard pictogramsGHS hazard statementsGHS precautionary statementsGadoliniumGalliumGallium(I) oxideGallium(III) oxideGanymede (moon)GasGas exchangeGas gangreneGas weldingGasolineGenesis (spacecraft)GeochemistryGeological history of oxygenGeology of solar terrestrial planetsGeorg Ernst StahlGeorge GobleGermaniumGermanium dioxideGermanium monoxideGillGlobally Harmonized System of Classification and Labelling of ChemicalsGlucoseGlutaraldehydeGlycerolGoldGold(III) oxideGraniteGreat Oxygenation EventGreen algaeGround stateGroup (periodic table)Group 10 elementGroup 11 elementGroup 12 elementGroup 3 elementGroup 4 elementGroup 5 elementGroup 6 elementGroup 7 elementGroup 8 elementGroup 9 elementHafniumHafnium(IV) oxideHalf-lifeHalogenHassiumHeat exchangerHeavy waterHeliumHelium-4Helium dimerHematiteHemeHemerythrinHemocyaninHemoglobinHerzberg continuumHexaoxygen difluorideHistory of atomic theoryHofmann voltameterHolmiumHolmium(III) oxideHugh ChisholmHumphry DavyHydrogenHydrogen bondHydrogen chlorideHydrogen peroxideHydrosphereHyperbaric medicineHyperbaric oxygen chamberHyperbaric treatment schedulesHyperoxiaHypersensitive responseHypofluorous acidHypoxia (environmental)Hypoxia (medical)Ibn al-NafisIce coreImmune systemIn Our Time (radio series)IndiumIndium(III) oxideInorganic compoundInternational Union of Pure and Applied ChemistryInvertebrateIodineIodine hexoxideIodine monoxideIodine pentoxideIodine tetroxideIonization energyIonizing radiationIridiumIridium(IV) oxideIronIron(II) oxideIron(II,III) oxideIron(III) oxideIron oreIron oxideIsopropyl alcoholIsotopeIsotopes of nitrogenIsotopes of oxygenJ. J. BecherJagiellonian UniversityJames DewarJohn DaltonJohn MayowJonathan ClaydenJoseph Louis Gay-LussacJoseph PriestleyJoule per moleKPaKarol OlszewskiKelvinKetoneKilojoule per moleKinematic viscosityKryptonLanthanumLanthanum oxideLattice constantLawrenciumLeadLeonardo da VinciLife-support systemLigandLimestoneLimiting oxygen concentrationLiquid airLiquid nitrogenLiquid oxygenList of chemical element name etymologiesList of data references for chemical elementsLiterLithiumLithium oxideLithium peroxideLithosphereLitreLivermoriumLouis Paul CailletetLow Earth orbitLungLutetiumLutetium(III) oxideMAPP gasMacrofaunaMagnesiumMagnesium oxideMagnesium peroxideMagnetMagnetic susceptibilityMagnetismManganeseManganese(II) oxideManganese(III) oxideManganese dioxideManganese heptoxideMarsMechanical ventilatorMedicineMeitneriumMelting pointMendeleviumMercuric oxideMercury(I) oxideMercury(II) oxideMercury (element)Metastability in moleculesMeteoriteMethanolMetre per secondMichael SendivogiusMichael ServetusMikhail EremetsMikhail LomonosovMilky Way GalaxyMitochondriaMmHgMolar fractionMolar heat capacity
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