Fluorine yog cov khoom siv tshuaj (cim F, atomic naj npawb 9), tsis yog hlau uas yog nyob rau hauv pawg halogens. Nws yog cov khoom nquag tshaj plaws thiab electronegative. Ntawm qhov kub thiab txias, cov fluorine molecule yog cov pa daj daj daj nrog cov mis F2. Zoo li lwm yam halides, molecular fluorine yog qhov txaus ntshai heev thiab ua rau muaj tshuaj lom neeg kub hnyiab ntawm daim tawv nqaij.
Siv
Fluorine thiab nws cov tebchaw tau siv dav, suav nrog rau kev tsim tshuaj, tshuaj agrochemicals, roj thiab roj nplua nyeem thiab textiles. Hydrofluoric acid yog siv los etch iav, thaum fluorine plasma yog siv los tsim semiconductors thiab lwm yam ntaub ntawv. Tsawg cov ntsiab lus ntawm F ions hauv cov tshuaj txhuam hniav thiab cov dej haus yuav pab tiv thaiv cov hniav caries, thaum muaj ntau dua muaj nyob rau hauv qee cov tshuaj tua kab. Feem ntau cov tshuaj loog yog hydrofluorocarbon derivatives. Lub isotope 18 F yog qhov chaw ntawm positrons rau kev kho mobpositron emission tomography imaging, thiab uranium hexafluoride yog siv los cais uranium isotopes thiab tsim enriched uranium rau nuclear fais fab nroj tsuag.
Discovery keeb kwm
Minerals uas muaj cov tshuaj fluorine tau paub ntau xyoo ua ntej kev sib cais ntawm cov tshuaj no. Piv txwv li, cov ntxhia fluorspar (los yog fluorite), muaj cov calcium fluoride, tau piav nyob rau hauv 1530 los ntawm George Agricola. Nws pom tias nws tuaj yeem siv los ua cov flux, ib yam khoom uas pab txo qhov melting point ntawm cov hlau los yog ore thiab pab ntxuav cov hlau xav tau. Yog li ntawd, fluorine tau txais nws lub npe Latin los ntawm lo lus fluere ("kom ntws").
Nyob rau xyoo 1670, lub tshuab iav Heinrich Schwanhard pom tias iav tau etched los ntawm kev ua ntawm calcium fluoride (fluorspar) kho nrog kua qaub. Carl Scheele thiab ntau tus kws tshawb fawb tom qab, suav nrog Humphry Davy, Joseph-Louis Gay-Lussac, Antoine Lavoisier, Louis Thénard, sim nrog hydrofluoric acid (HF), uas tau yooj yim tau los ntawm kev kho CaF nrog concentrated sulfuric acid.
Thaum kawg, nws tau pom tseeb tias HF muaj cov khoom tsis paub yav dhau los. Txawm li cas los xij, vim nws cov reactivity ntau dhau, cov tshuaj no tsis tuaj yeem raug cais tawm tau ntau xyoo. Nws tsis yog tsuas yog nyuaj rau cais tawm ntawm cov tebchaw, tab sis tam sim ntawd reacts nrog lawv lwm yam Cheebtsam. Kev cais tawm ntawm cov tshuaj fluorine los ntawm hydrofluoric acid yog qhov txaus ntshai heev, thiab kev sim ntxov ua rau dig muag thiab tua ntau tus kws tshawb fawb. Cov neeg no tau hu ua "martyrsfluorine."
Tshawb nrhiav thiab tsim khoom
Thaum kawg, xyoo 1886, Fab Kis tus kws kho mob Henri Moissan tau tswj hwm cais cov tshuaj fluorine los ntawm electrolysis ntawm kev sib xyaw ntawm molten potassium fluorides thiab hydrofluoric acid. Rau qhov no nws tau txais 1906 Nobel nqi zog hauv Chemistry. Nws txoj hauv kev electrolytic tseem siv niaj hnub no rau kev tsim khoom ntawm cov tshuaj no.
Thawj qhov loj ntawm cov tshuaj fluorine tau pib thaum Tsov Rog Ntiaj Teb Zaum II. Nws tau xav tau rau ib qho ntawm cov theem ntawm kev tsim lub foob pob atomic raws li ib feem ntawm Manhattan Project. Fluorine tau siv los tsim uranium hexafluoride (UF 6), uas tau siv los cais ob isotopes 235 U thiabntawm ib leeg. 238U. Niaj hnub no, gaseous UF6 yog xav tau los tsim uranium enriched rau nuclear fais fab.
Cov khoom tseem ceeb tshaj plaws ntawm fluorine
Nyob rau hauv lub sij hawm lub sij hawm, lub caij yog nyob rau sab saum toj ntawm pab pawg neeg 17 (yav tas los pab pawg neeg 7A), uas yog hu ua halogen. Lwm cov halogens muaj xws li chlorine, bromine, iodine thiab astatine. Tsis tas li ntawd, F yog nyob rau lub sijhawm thib ob ntawm oxygen thiab neon.
Ntshiab fluorine yog cov roj corrosive (cov tshuaj formula F2) nrog cov yam ntxwv pungent tsw uas pom nyob rau ntawm ib tug concentration ntawm 20 nl ib liter ntawm ntim. Raws li feem ntau reactive thiab electronegative ntawm tag nrho cov ntsiab lus, nws yooj yim tsim cov tebchaw nrog feem ntau ntawm lawv. Fluorine yog reactive heev kom muaj nyob rau hauv lub cev thiab muaj xws liKev sib raug zoo nrog cov ntaub ntawv feem ntau, suav nrog silicon, uas nws tsis tuaj yeem npaj lossis khaws cia hauv cov thawv iav. Hauv huab cua ntub, nws hnov mob nrog dej los tsim cov hydrofluoric acid txaus ntshai.
Fluorine, cuam tshuam nrog hydrogen, tawg txawm tias qhov kub thiab txias. Nws reacts hnyav nrog dej los tsim hydrofluoric acid thiab oxygen gas. Ntau yam ntaub ntawv, suav nrog cov hlau thiab cov tsom iav zoo nkauj, hlawv nrog cov nplaim ci ntsa iab hauv lub dav hlau ntawm cov roj fluorine. Tsis tas li ntawd, cov khoom siv tshuaj no tsim cov tebchaw nrog cov pa roj krypton, xenon thiab radon. Txawm li cas los xij, nws tsis cuam tshuam ncaj qha nrog nitrogen thiab oxygen.
Txawm hais tias muaj kev ua haujlwm hnyav ntawm fluorine, txoj hauv kev rau nws txoj kev nyab xeeb thiab kev thauj mus los tau tam sim no muaj. Cov khoom yuav raug muab khaws cia rau hauv cov hlau lossis monel (nickel-nplua nuj alloy) ntim, raws li cov tshuaj fluorides tsim rau ntawm cov ntaub ntawv no, uas tiv thaiv cov tshuaj tiv thaiv ntxiv.
Fluorides yog cov tshuaj uas muaj fluorine tam sim no ua qhov tsis zoo ion (F-) ua ke nrog qee cov ntsiab lus zoo. Cov tshuaj fluorine nrog cov hlau yog cov ntsev ruaj khov tshaj plaws. Thaum yaj hauv dej, lawv muab faib ua ions. Lwm hom fluorine yog cov complexes, piv txwv li, [FeF4-, thiab H2F +.
Isotopes
Muaj ntau cov isotopes ntawm no halogen, xws li ntawm 14 F mus 31F. Tab sis cov isotopic muaj pes tsawg leeg ntawm fluorine suav nrog tsuas yog ib qho ntawm lawv,19F, uas muaj 10 neutrons, vim nws tsuas yog ib qho uas ruaj khov. Cov xov tooj cua isotope 18 F yog qhov muaj txiaj ntsig ntawm positrons.
Kev cuam tshuam txog kab mob lom neeg
Fluorine nyob rau hauv lub cev feem ntau pom muaj nyob rau hauv cov pob txha thiab cov hniav nyob rau hauv daim ntawv ntawm ions. Fluoridation ntawm cov dej haus ntawm ib tug concentration ntawm tsawg tshaj li ib feem ntawm ib lab ho txo qhov tshwm sim ntawm caries - raws li National Research Council ntawm National Academy of Sciences ntawm lub tebchaws United States. Ntawm qhov tod tes, cov tshuaj fluoride ntau dhau tuaj yeem ua rau fluorosis, uas tshwm sim nws tus kheej hauv cov hniav mottled. Cov nyhuv no feem ntau pom nyob rau hauv cov cheeb tsam uas cov ntsiab lus ntawm cov tshuaj no nyob rau hauv cov dej haus ntau tshaj 10 ppm.
Cov tshuaj fluorine thiab fluoride ntsev yog tshuaj lom thiab yuav tsum tau saib xyuas zoo. Kev sib cuag nrog daim tawv nqaij lossis qhov muag yuav tsum ua tib zoo zam. Cov tshuaj tiv thaiv ntawm daim tawv nqaij tsim hydrofluoric acid, uas sai sai nkag mus rau hauv cov ntaub so ntswg thiab reacts nrog calcium nyob rau hauv cov pob txha, ua rau lawv mus tas li.
Ib puag ncig fluorine
Lub ntiaj teb txhua xyoo tsim cov ntxhia fluorite yog kwv yees li 4 lab tons, thiab tag nrho cov peev txheej ntawm kev tshawb nrhiav tso nyiaj yog nyob rau hauv 120 lab tons. Cov chaw mining tseem ceeb rau cov pob zeb no yog Mexico, Tuam Tshoj thiab Western Europe.
Fluorine tshwm sim nyob rau hauv lub ntiaj teb crust, qhov twg nws muaj peev xwm pom nyob rau hauv pob zeb, thee thiab av nplaum. Cov fluoride raug tso tawm rau saum huab cua los ntawm cua yaig ntawm cov av. Fluorine yog 13th feem ntau cov tshuaj lom neeg nyob rau hauv lub ntiaj teb crust - nws cov ntsiab lusua 950ppm. Hauv cov av, nws qhov nruab nrab concentration yog li 330 ppm. Hydrogen fluoride tuaj yeem tso tawm rau hauv huab cua raws li kev lag luam combustion txheej txheem. Cov fluorides uas nyob rau hauv cov huab cua yuav poob mus rau hauv av los yog mus rau hauv dej. Thaum fluorine bonds nrog cov khoom me me, nws tuaj yeem nyob hauv huab cua ntev ntev.
Nyob rau hauv cov huab cua, 0.6 billionths ntawm cov tshuaj no muaj nyob rau hauv daim ntawv ntawm ntsev pos thiab organic chlorine tebchaw. Hauv nroog, qhov concentration nce mus txog 50 feem ntawm ib billion.
Kev sib txuas
Fluorine yog cov tshuaj lom neeg uas tsim muaj ntau yam organic thiab inorganic compounds. Chemists tuaj yeem hloov cov hydrogen atoms nrog nws, yog li tsim ntau yam tshiab. Highly reactive halogen forms tebchaw nrog noble gases. Xyoo 1962, Neil Bartlett tau tsim cov xenon hexafluoroplatinate (XePtF6). Krypton thiab radon fluorides kuj tau txais. Lwm qhov sib xyaw yog argon fluorohydride, uas ruaj khov tsuas yog ntawm qhov kub tsis tshua muaj siab.
Industrial applications
Nyob rau hauv nws lub xeev atomic thiab molecular, fluorine yog siv rau plasma etching nyob rau hauv zus tau tej cov semiconductors, tiaj vaj huam sib luag zaub, thiab microelectromechanical systems. Hydrofluoric acid yog siv los etch iav hauv teeb thiab lwm yam khoom.
Nrog rau qee qhov sib txuas, fluorine yog ib qho tseem ceeb hauv kev tsim tshuaj, tshuaj agrochemicals, roj thiab roj nplua nyeem.cov ntaub ntawv thiab textiles. Cov khoom siv tshuaj yog xav tau los tsim cov halogenated alkanes (halons), uas, nyob rau hauv lem, tau dav siv nyob rau hauv lub tshuab cua txias thiab tub yees. Tom qab ntawd, xws li kev siv chlorofluorocarbons raug txwv vim tias lawv ua rau kev puas tsuaj ntawm cov txheej txheem ozone nyob rau saum huab cua.
Sulfur hexafluoride yog ib qho tsis tshua muaj zog, tsis muaj tshuaj lom cov pa uas tau muab cais ua cov pa hauv tsev cog khoom. Yog tias tsis muaj fluorine, kev tsim cov khoom siv qis qis xws li Teflon tsis tuaj yeem ua tau. Ntau yam tshuaj loog (xws li sevoflurane, desflurane thiab isoflurane) yog CFC derivatives. Sodium hexafluoroaluminate (cryolite) yog siv hauv txhuas electrolysis.
Fluoride compounds, suav nrog NaF, yog siv rau hauv cov tshuaj txhuam hniav los tiv thaiv cov hniav lwj. Cov tshuaj no tau ntxiv rau hauv cov dej hauv nroog los muab cov dej fluoridation, txawm li cas los xij qhov kev coj ua yog suav tias muaj teeb meem vim muaj kev cuam tshuam rau tib neeg kev noj qab haus huv. Ntawm qhov siab dua, NaF yog siv los ua tshuaj tua kab, tshwj xeeb tshaj yog rau kev tswj kab laum.
Yav dhau los, fluorides tau siv los txo qhov melting point ntawm hlau thiab ore thiab ua kom lawv fluidity. Fluorine yog ib qho tseem ceeb hauv kev tsim cov uranium hexafluoride, uas yog siv los cais nws cov isotopes. 18F, lub xov tooj cua isotope nrog ib nrab-lub neej ntawm 110 feeb, emits positrons thiab feem ntau siv hauv kev kho mob positron emission tomography.
Lub cev muaj zog ntawm fluorine
Cov yam ntxwv tseem ceebCov khoom siv tshuaj lom neeg raws li hauv qab no:
- Atomic huab hwm coj 18.9984032 g/mol.
- Electronic configuration 1s22s22p5.
- Oxidation xeev -1.
- Density 1.7 g/L.
- Melting point 53.53 K.
- Boiling Point 85.03 K.
- Heat peev 31.34 J/(K mol).
