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HydrogenandIndustries

Hydrogen,thelightestandsimplestoftheelements,hasseveralpropertiesthatmakeitvaluableformanyindustries.Itreleasesmoreheatperunitofweightthananyotherfuel.Inrocketengines,tonsofhydrogenandoxygenareburned,andhydrogenisusedwithoxygenforweldingtorchesthatproducetemperaturesashighas4,000degreesFandcanbeusedincuttingsteel.Fuelcellstogenerateelectricityoperateonhydrogenandoxygen.

Hydrogenalsoservestopreventmetalsfromtarnishingduringheattreatmentsbyremovingtheoxygenfromthem.Althoughitwouldbedifficulttoremovetheoxygenbyitself,hydrogenreadilycombineswithoxygentoformwater,whichcanbeheatedtosteamandeasilyremoved.Hydrogenisalsousefulinthefoodindustryforaprocessknowashydrogenation.Productssuchasmargarineandcookingoilsarechangedfromliquidstosemisolidsbyaddinghydrogentotheirmolecules.Soapmanufacturersalsousehydrogenforthispurpose.

Hydrogenisalsooneofthecoolestrefrigerants.Itdoesnotbecomealiquiduntilitreachestemperaturesof-425degreesF.Purehydrogengasisusedinlargeelectricgeneratorstocoolthecoils.Inaddition,inthechemicalindustry,hydrogenisusedtoproduceammonia,gasoline,methylalcohol,andmanyotherimportantproducts.

氫與工業(yè)

氫作為最輕和最簡樸的無素，有幾種特性對工業(yè)分外有用。作為燃料，它每單位重量釋放熱量最多，在火箭的引擎中，成噸的氫和氧被燃燒掉。氫和氧合在一起用于焊接，能夠產(chǎn)生高達華氏四千度的高溫而可以切割鋼鐵。發(fā)電的燃料房就是使用氫和氧。

氫也可以用來在金屬熱處理中通過從中除去氧的方法來防銹。雖然單獨除去氧本身是困難的，氫和氧很輕易結(jié)合成水，而水是可以加熱蒸發(fā)除去的。氫在食品工業(yè)中對于所謂的氫化過程也很有用。人造黃油和食用油的分子中加上氫，就由液態(tài)變成半固態(tài)。肥皂制造商也為