Txhua tus neeg ntsib kev coj noj coj ua ntawm nws tsev neeg nrog cov xwm txheej zoo li xeb. Nws paub tias nws yog qhov tshwm sim ntawm hlau oxidation.
xeb ua li cas?
Txhua yam khoom siv hlau muaj qee yam ntawm cov hlau: steel, ligature, thiab lwm yam. Nws koom nrog ntau cov txheej txheem thev naus laus zis kom tau txais ntau yam hlau. Cov hlau muaj nyob rau hauv lub ntiaj teb crust. Cov hlau no tau ntxiv thaum lub sijhawm tsim khoom ntawm ntau hom khoom, thiab nws yuav luag tsis tuaj yeem tshem tawm tag nrho, thiab qee zaum nws tsis tsim nyog. Cov khoom no, tam sim no nyob rau hauv cov khoom hlau, oxidizes lub sij hawm nyob rau hauv qhov kev txiav txim ntawm huab cua, noo noo, dej, thiab yog li ntawd, hlau oxide 3 daim ntawv nyob rau saum npoo.
Basic nta
Iron oxide yog cov hlau uas muaj xim zoo nkauj heev. Nws qiv nws tus kheej zoo rau ntau hom kev siv tshuab: forging, dov. Nws muaj peev xwm ua kom yaj ntau lub ntsiab lus hauv nws tus kheej tau pom dav siv hauv kev tsim ntau cov alloys. Cov tshuaj no cuam tshuamnrog yuav luag tag nrho cov dilute acids, tsim cov tebchaw ntawm tus coj valency. Tab sis nyob rau hauv concentrated acids, nws coj heev passively. Cov hlau ntshiab yog tau los ntawm kev ua haujlwm ntawm cov khoom siv ntxhia, hauv cov hlau oxide feem ntau yog tam sim no.
Kev sib txuas
Iron forms compounds of two series: 2-valent and 3-valent compounds. Txhua yam ntawm lawv characterizes nws oxide. Hlau tebchaw yog tsim los ntawm dissolving nyob rau hauv acids. Hlau ntsev 3 muaj zog hydrolyzed, yog li lawv muaj xws li xim daj-xim av, txawm hais tias lub caij nws tus kheej tsis muaj xim. Hlau tebchaw yog dav siv nyob rau hauv metallurgy raws li kev txo cov neeg sawv cev, nyob rau hauv lub teb chaws kev lag luam rau kev tswj kab tsuag, nyob rau hauv textile kev lag luam, thiab lwm yam. Anhydrous hlau oxide 2 yog tau los ntawm oxide 3 los ntawm kev txo qis raws li ib tug dub hmoov, thaum hlau oxide 3 yog tau los ntawm calcination ntawm hlau hydroxide 3. Oxides tsim lub hauv paus rau kev npaj ntawm hlau ntsev. Kuj tseem muaj cov ntsiab lus me me ntawm cov kua qaub no thiab cov sib txuas nrog qhov valence ntawm +6. Thaum oxide 3 yog fused, ferrites thiab ferrates raug tsim, tshiab, tseem tsis tau kawm zoo heev.
Cov ntsiab lus piav qhia thiab nws cov ntsiab lus tau nthuav dav hauv qhov xwm txheej. Hlau oxide 3 muaj nyob rau hauv daim ntawv ntawm liab, xim av hlau ore, thiab Fe3O4 yog pom nyob rau hauv daim ntawv ntawm hlau nplaum hlau ore. Rau kev tsim cov sulfuric acid, hlau pyrite (sulfide) yog siv. Oxides yog lub hauv paus ntawm cov hlau thiabnrum hlau. Hlau thiab cam khwb cia hlau muaj roughly tib yam muaj pes tsawg leeg, qhov txawv tsuas yog cov ntsiab lus carbon. Hlau alloys uas muaj tsawg dua 2.14% carbon yog hu ua steels, thiab ntau tshaj 2.14% - cam khwb cia hlau. Qhov kev faib tawm no tsis haum rau cov hlau nyuaj xws li cov hlau alloy vim tias lawv muaj ntau dua thiab muaj cov ntsiab lus ntxiv.
