# liquid oxyge contributors to wikimedia project 9–11 minute from wikipedia the free encyclopedi this article is about the liquid form of the element oxygen. for the commercial dietary supplement product see liquid oxygen (supplement ![[liquidoxygeninabeaker(croppedandretouched)1dpr.jpg|300]] liquid oxygen (o2) (cyan liquid) in a beake ![[liquidoxygeninamagnet21dpr.jpg|300]] when liquid oxygen (o2) is poured from a beaker into a strong magnet the oxygen is temporarily suspended between the magnet poles owing to its paramagnetis liquid oxygen sometimes abbreviated as lox or loxygen is a clear pale cyan liquid form of dioxygen o2. it was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by robert h. goddard an application which is ongoin ## physical propertie liquid oxygen has a clear pale cyan color and is strongly paramagnetic: it can be suspended between the poles of a powerful horseshoe magnet. liquid oxygen has a density of 1.141kg/l (1.141g/ml) slightly denser than liquid water and is cryogenic with a freezing point of 54.36k (−218.79°c; −361.82°f) and a boiling point of 90.19k (−182.96°c; −297.33°f) at 1bar (14.5psi). liquid oxygen has an expansion ratio of 1: 861 and because of this it is used in some commercial and military aircraft as a transportable source of breathing oxyge liquid oxygen is also a very powerful oxidizing agent: organic materials will burn rapidly and energetically in liquid oxygen. further if soaked in liquid oxygen some materials such as coal briquettes carbon black etc. can detonate unpredictably from sources of ignition such as flames sparks or impact from light blows. petrochemicals including asphalt often exhibit this behavio the tetraoxygen molecule (o4) was predicted in 1924 by gilbert n. lewis who proposed it to explain why liquid oxygen defied curie's law. modern computer simulations indicate that although there are no stable o4 molecules in liquid oxygen o2 molecules do tend to associate in pairs with antiparallel spins forming transient o4 unit liquid nitrogen has a lower boiling point at −196°c (77k) than oxygen's −183°c (90k) and vessels containing liquid nitrogen can condense oxygen from air: when most of the nitrogen has evaporated from such a vessel there is a risk that liquid oxygen remaining can react violently with organic material. conversely liquid nitrogen or liquid air can be oxygen-enriched by letting it stand in open air; atmospheric oxygen dissolves in it while nitrogen evaporates preferentiall the surface tension of liquid oxygen at its normal pressure boiling point is 13.2dyn/cm (13.2mn/m ![[liquidoxygenbagramairfieldafghanistan41dpr.jpg|300]] a u.s. air force technician transfers liquid oxygen to a lockheed martin c-130j super hercules aircraft at the bagram airfield afghanista ![[liquidoxygentank1dpr.jpg|300]] liquid oxygen tank at national hospital (teaching) kand in commerce liquid oxygen is classified as an industrial gas and is widely used for industrial and medical purposes. liquid oxygen is obtained from the oxygen found naturally in air by fractional distillation in a cryogenic air separation plan ![[liquidoxygen1dpr.png|300]] insulated evaporator and storage container setup for liquid oxyge air forces hav long recognized the strategic importance of liquid oxygen both as an oxidizer and as a supply of gaseous oxygen for breathing in hospitals and high-altitude aircraft flights. in 1985 the usaf started a program of building its own oxygen-generation facilities at all major consumption base ## in rocket propellan ![[liquidoxygen(lox)ballattheccafsslc-401dpr.jpg|300]] spacex's liquid oxygen ball at cape canavera liquid oxygen is the most common cryogenic liquid oxidizer propellant for spacecraft propulsion applications usually in combination with liquid hydrogen kerosene or methan liquid oxygen was used in the first liquid fueled rocket. the world war ii v-2 missile also used liquid oxygen under the name a-stoff and sauerstoff. in the 1950s during the cold war both the united states' redstone and atlas rockets and the soviet r-7 semyorka used liquid oxygen. later in the 1960s and 1970s the ascent stages of the apollo saturn rockets and the space shuttle main engines used liquid oxyge as of 2026 many active rockets use liquid oxygen **+** chinese space progra - casc: long march (rocket family - operational: long march -5 -5b -6 -6a -6c -7 -7a -8 -8a -10b -12 -12a -12 - under development: -9 -10 -10 - cas space: kinetica - deep blue aerospace: nebula-1 (under development - galactic energy: pallas-1 (under development - i-space: hyperbola-3 (under development - landspace: zhuque-2e zhuque- - orienspace: gravity-2 (under development - space epoch: yuanxingzhe-1 (under development - space pioneer: tianlong-2 tianlong- **+** europ - european space agency: ariane - isar aerospace: spectrum (under development - pld space: miura 5 (under development - rocket factory augsburg: rfa one (under development **+** indian space research organisation: gslv lvm **+** jaxa (japan): h **+** korea aerospace research institute: nur **+** roscosmos (russia): soyuz-2 angara soyuz- **+** united state - blue origin: new glen - firefly aerospace: firefly alph - nasa: space launch syste - northrop grumman: antares 300 (under development - relativity space: terran r (under development - rocket lab: electron neutron (under development - spacex: falcon 9 falcon heavy starshi - stoke space: nova (under development - united launch alliance: atlas v vulca **+** by 1845 michael faraday had managed to liquefy most gases then known to exist. six gases however resisted every attempt at liquefaction and were known at the time as "permanent gases". they were oxygen hydrogen nitrogen carbon monoxide methane and nitric oxide **+** in 1877 louis paul cailletet in france and raoul pictet in switzerland succeeded in producing the first droplets of liquid air **+** in 1883 polish professors zygmunt wróblewski and karol olszewski produced the first measurable quantity of liquid oxyge **+** oxygen storag **+** industrial ga **+** cryogenic **+** liquid hydroge **+** liquid heliu **+** liquid nitroge **+** list of stoff **+** natterer compresso **+** rocket fue **+** solid oxyge **+** tetraoxyge 1. ↑ "first liquid-fueled rocket". history. retrieved 2019-03-16 2. ↑ moore john w.; stanitski conrad l.; jurs peter c. (21 january 2009). principles of chemistry: the molecular science. cengage learning. pp.297–. isbn978-0-495-39079-4. retrieved 3 april 2011 3. ↑ cryogenic safety. chemistry.ohio-state.edu 4. ↑ characteristics. archived 2012-02-18 at the wayback machine. lindecanada.com. retrieved on 2012-07-22 5. ↑ "liquid oxygen receipt handling storage and disposal". usaf training film 6. ↑ lewis gilbert n. (1924). "the magnetism of oxygen and the molecule o2". journal of the american chemical society. 46 (9): 2027–2032. doi: 10.1021/ja01674a008 7. ↑ oda tatsuki; alfredo pasquarello (2004). "noncollinear magnetism in liquid oxygen: a first-principles molecular dynamics study". physical review b. 70 (134402): 1–19. bibcode: 2004phrvb..70m4402o. doi: 10.1103/physrevb.70.134402. hdl: 2297/3462. s2cid123535786 8. ↑ j.m. jurns and j.w. hartwig (2011). liquid oxygen liquid acquisition device bubble point tests with high pressure lox at elevated temperatures p.4 9. ↑ arnold mark. 1u.s. army oxygen generation system development. rto-mp-hfm-182. dtic.mi 10. ↑ timmerhaus k. d. (8 march 2013). advances in cryogenic engineering: proceedings of the 1957 cryogenic engineering conference national bureau of standards boulder colorado august 19–21 1957. springer science & business media. pp.150–. isbn978-1-4684-3105-6 11. ↑ belluscio alejandro g. (march 7 2014). "spacex advances drive for mars rocket via raptor power". nasaspaceflight.com. retrieved march 13 2014 12. ↑ todd david (november 20 2012). "musk goes for methane-burning reusable rockets as step to colonise mars". flightglobal hyperbola. archived from the original on november 28 2012. retrieved november 22 2012. "we are going to do methane" musk announced as he described his future plans for reusable launch vehicles including those designed to take astronauts to mars within 15 years. "the energy cost of methane is the lowest and it has a slight isp (specific impulse) advantage over kerosene" said musk adding "and it does not hav the pain in the ass factor that hydrogen has." ... spacex's initial plan will be to build a lox/methane rocket for a future upper stage codenamed raptor. ... the new raptor upper stage engine is likely to be only the first engine in a series of lox/methane engines 13. ↑ cryogenics. scienceclarified.com. retrieved on 2012-07-22 14. ↑ papanelopoulou faidra (2015). louis paul cailletet the liquefaction of oxygen and the emergence of an `in-between discipline': low-temperature research. springer international publishing. pp.9–22. isbn978-3-319-14553-2 15. ↑ kubbinga henk (2010) "a tribute to wróblewski and olszewski" europhysics news 41 (4): 21–24 doi: 10.1051/epn/201040 **+** schmidt eckart w. (2022). "oxygen". encyclopedia of oxidizers. de gruyter. pp.3053–3218. doi: 10.1515/9783110750294-025. isbn978-3-11-075029-4.