Arsenic yog cov tshuaj lom neeg ntawm pawg nitrogen (pab pawg 15 ntawm lub sijhawm teem sijhawm). Qhov no yog cov khoom siv tawv tawv (α-arsenic) grey nrog lub ntsej muag xim hlau nrog lub rhombohedral siv lead ua lattice. Thaum rhuab mus rau 600 ° C, Raws li sublimates. Thaum lub vapor txias, qhov hloov tshiab tshwm sim - daj arsenic. Tshaj 270 ° C, tag nrho Raws li cov ntaub ntawv hloov mus ua arsenic dub.
Discovery keeb kwm
Arsenic tau paub ntev ua ntej nws tau lees paub tias yog tshuaj lom neeg. Nyob rau hauv lub xyoo pua IV. BC e. Aristotle tau hais txog ib yam khoom hu ua sandarak, uas tam sim no ntseeg tau tias yog realgar, lossis arsenic sulfide. Thiab nyob rau xyoo pua 1 A. D. e. cov kws sau ntawv Pliny tus Txwj Laug thiab Pedanius Dioscorides tau piav qhia txog orpiment - lub dye As2S3. Nyob rau hauv lub xyoo pua XI. n. e. Peb hom "arsenic" tau txawv: dawb (As 4 O 6), daj (As2 S 3) thiab liab (As4S4). Lub caij nws tus kheej yog thawj zaug cais nyob rau hauv lub xyoo pua 13th los ntawm Albert the Great, uas tau sau tseg cov tsos ntawm cov khoom zoo li hlau thaum arsenicum, lwm lub npe As2S3. , tau rhaub nrog xab npum. Tab sis tsis muaj qhov tseeb tias tus kws tshawb fawb ntuj no tau txais cov arsenic ntshiab. Thawj qhov pov thawj tseeb ntawm kev sib cais ntawm cov tshuaj dawb huvua 1649. Tus kws muag tshuaj German Johann Schroeder tau npaj arsenic los ntawm cua sov nws cov oxide nyob rau hauv lub xub ntiag ntawm thee. Tom qab ntawd, Nicolas Lemery, tus kws kho mob Fab Kis thiab kws tshuaj, tau soj ntsuam qhov tsim ntawm cov tshuaj no los ntawm kev sib xyaw ntawm nws cov oxide, xab npum thiab potash. Thaum pib ntawm lub xyoo pua 18th, arsenic twb paub tias yog ib qho semimetal tshwj xeeb.
Nyob zoo
Nyob rau hauv lub ntiaj teb crust, qhov concentration ntawm arsenic yog tsawg thiab muaj li 1.5 ppm. Nws tshwm sim hauv av thiab cov zaub mov thiab tuaj yeem tso tawm rau hauv huab cua, dej thiab av los ntawm cua thiab dej yaig. Tsis tas li ntawd, lub caij nkag mus rau hauv huab cua los ntawm lwm qhov chaw. Raws li qhov tshwm sim ntawm volcanic eruptions, kwv yees li 3 txhiab tons ntawm arsenic raug tso tawm rau saum huab cua hauv ib xyoos, cov kab mob tsim 20 txhiab tons ntawm cov tshuaj methylarsine tsis zoo nyob rau ib xyoos, thiab vim li cas cov roj fossil hlawv, 80 txhiab tons raug tso tawm tib lub sijhawm..
Txawm tias muaj tshuaj lom neeg tuag taus, nws yog ib feem tseem ceeb ntawm kev noj zaub mov ntawm qee cov tsiaj thiab tej zaum tib neeg, txawm tias qhov koob tshuaj yuav tsum tsis pub tshaj 0.01 mg / hnub.
Arsenic nyuaj heev los hloov mus rau hauv dej-soluble lossis volatile xeev. Qhov tseeb tias nws yog mobile heev txhais tau hais tias cov concentrations loj ntawm cov khoom nyob rau hauv ib qho chaw tsis tuaj yeem tshwm sim. Ntawm ib sab, qhov no yog qhov zoo, tab sis ntawm qhov tod tes, qhov yooj yim uas nws kis tau yog vim li cas vim li cas arsenic muaj kuab paug dhau los ua teeb meem loj. Vim tib neeg kev ua ub no, feem ntau yog los ntawm kev tsuas thiab smelting, ib txwm immobile chemical keeb migrate, thiab tam sim no nws muaj peev xwm pom tsis tau tsuas yog nyob rau hauv cov chaw.nws natural concentration.
Tus nqi ntawm arsenic nyob rau hauv lub ntiaj teb crust yog hais txog 5 g ib ton. Hauv qhov chaw, nws cov concentration yog kwv yees li ntawm 4 atoms ib lab silicon atoms. Cov ntsiab lus no yog dav. Ib qho me me tam sim no nyob rau hauv lub xeev haiv neeg. Raws li txoj cai, tsim ntawm arsenic nrog purity ntawm 90-98% yog pom ua ke nrog hlau xws li antimony thiab nyiaj. Feem ntau ntawm nws, txawm li cas los xij, suav nrog ntau dua 150 cov zaub mov sib txawv - sulfides, arsenides, sulfoarsenides thiab arsenites. Arsenopyrite FeAsS yog ib qho ntawm cov khoom muaj txiaj ntsig zoo tshaj plaws. Lwm cov arsenic sib xyaw ua ke yog cov ntxhia pob zeb As4 s 4, orpiment As 2 S3, lellingite FeAs2 and enargite Cu3AsS4. Arsenic oxide kuj muaj ntau. Feem ntau ntawm cov khoom no yog cov khoom los ntawm smelting tooj liab, lead, cob alt thiab kub ores.
Hauv qhov xwm txheej, tsuas muaj ib qho isotope ruaj khov ntawm arsenic - 75 As. Ntawm cov hluav taws xob hluav taws xob hluav taws xob, 76 Raws li nrog ib nrab-lub neej ntawm 26.4 teev sawv tawm. Arsenic-72, -74 thiab -76 yog siv hauv kev kuaj mob.
Industrial ntau lawm thiab daim ntawv thov
Hlau arsenic yog tau los ntawm cua sov arsenopyrite rau 650-700 ° C yam tsis muaj cua. Yog hais tias arsenopyrite thiab lwm yam hlau ore yog rhuab nrog oxygen, ces Raws li yooj yim nkag mus rau hauv ua ke nrog nws, tsim tau yooj yim sublimated As4 O 6, kuj paub. zoo li "dawbarsenic". Cov oxide vapor yog sau thiab condensed, thiab tom qab ntawd purified los ntawm resublimation. Feem ntau Raws li yog tsim los ntawm carbon txo los ntawm dawb arsenic yog li tau.
Ntiaj teb kev noj cov hlau arsenic tsawg tsawg - tsuas yog ob peb puas tons hauv ib xyoos. Feem ntau ntawm cov khoom noj yog los ntawm Sweden. Nws yog siv nyob rau hauv metallurgy vim nws metalloid zog. Kwv yees li 1% arsenic yog siv rau hauv kev tsim cov hlau lead txhaj tshuaj, vim nws txhim kho lub roundness ntawm molten poob. Cov khoom ntawm cov hlau lead-based bearing alloys txhim kho ob qho tib si thermally thiab mechanically thaum lawv muaj li 3% arsenic. Lub xub ntiag ntawm me me ntawm cov tshuaj no nyob rau hauv cov hlau lead alloys hardens lawv siv nyob rau hauv cov roj teeb thiab cable armor. Me me impurities ntawm arsenic nce corrosion kuj thiab thermal zog ntawm tooj liab thiab tooj dag. Nyob rau hauv nws daim ntawv ntshiab, tshuaj elemental Raws li yog siv rau bronze plating thiab nyob rau hauv pyrotechnics. Highly purified arsenic pom siv nyob rau hauv semiconductor technology, qhov twg nws yog siv nrog silicon thiab germanium, thiab nyob rau hauv daim ntawv ntawm gallium arsenide (GaAs) nyob rau hauv diodes, lasers thiab transistors.
Kev sib txuas As
Vim qhov muaj txiaj ntsig ntawm arsenic yog 3 thiab 5, thiab nws muaj ntau lub xeev oxidation los ntawm -3 txog +5, lub caij tuaj yeem tsim ntau yam sib txuas. Qhov tseem ceeb tshaj plaws ntawm kev lag luam yog nws cov oxides, cov ntaub ntawv tseem ceeb uas yog As 4O6 thiabAs2O5. Arsenic oxide, feem ntau hu ua dawb arsenic, yog ib qho khoom los ntawm cov khoom ci ntawm tooj liab, txhuas, thiab lwm yam hlau, nrog rau arsenopyrite thiab sulfide ores. Nws yog cov khoom pib rau feem ntau lwm cov tebchaw. Tsis tas li ntawd, nws yog siv nyob rau hauv tshuaj tua kab, raws li ib tug bleaching neeg sawv cev nyob rau hauv iav ntau lawm, thiab raws li ib tug preservative rau tawv. Arsenic pentoxide yog tsim los ntawm kev ua ntawm oxidizing tus neeg sawv cev (piv txwv li, nitric acid) ntawm dawb arsenic. Nws yog cov khoom tseem ceeb hauv tshuaj tua kab, tshuaj tua kab thiab hlau nplaum.
Arsine (AsH3), cov roj tsis muaj xim tsis muaj tshuaj lom uas muaj arsenic thiab hydrogen, yog lwm yam khoom paub. Cov khoom, tseem hu ua arsenic hydrogen, yog tau los ntawm hydrolysis ntawm hlau arsenides thiab txo cov hlau los ntawm arsenic tebchaw nyob rau hauv acid daws. Nws tau pom tias siv los ua ib qho dopant hauv semiconductors thiab ua tub rog lom roj. Hauv kev ua liaj ua teb, arsenic acid (H3AsO4), lead arsenate (PbHAsO44 4) thiab calcium arsenate [Ca3(AsO4)2
], uas yog siv los ua kom tsis muaj av thiab tshuaj tua kab.
Arsenic yog cov tshuaj lom neeg uas tsim ntau cov organic sib txuas. HowOne (CH3)2As-As(CH3)2 , piv txwv li, yog siv rau hauv kev npaj cov khoom siv dav dav (desiccant) - cacodylic acid. Complex organic compounds ntawm lub caij yog siv nyob rau hauv kev kho mob ntawm tej yam kab mob, piv txwv li, amoebic dysentery,tshwm sim los ntawm kab mob.
Lub cev muaj zog
Dab tsi yog arsenic ntawm nws lub cev lub zog? Nyob rau hauv nws lub xeev ruaj khov tshaj plaws, nws yog nkig, steely grey khoom nrog tsawg thermal thiab hluav taws xob conductivity. Txawm hais tias qee cov ntaub ntawv ntawm As yog hlau zoo li, cais nws raws li cov hlau tsis yog hlau yog qhov tseeb dua tus yam ntxwv ntawm arsenic. Muaj lwm hom arsenic, tab sis lawv tsis tau kawm zoo, tshwj xeeb tshaj yog cov daj metastable daim ntawv, muaj xws li As4 molecules, zoo ib yam li dawb phosphorus P 4. Arsenic sublimates ntawm 613 ° C thiab muaj nyob rau hauv vapor li As4 molecules uas tsis sib cais txog li 800 ° C. Ua kom tiav dissociation rau hauv As2 molecules tshwm sim ntawm 1700 °C.
Tus qauv ntawm lub atom thiab lub peev xwm los tsim daim ntawv cog lus
Cov mis hluav taws xob ntawm arsenic yog 1s22s22p63s 23p63d104s24p 3 - zoo ib yam li nitrogen thiab phosphorus nyob rau hauv uas nws muaj tsib electrons nyob rau hauv lub plhaub, tab sis nws txawv ntawm lawv los ntawm muaj 18 electrons nyob rau hauv lub penultimate plhaub es tsis txhob ntawm ob los yog yim. Qhov sib ntxiv ntawm 10 tus nqi zoo hauv lub nucleus thaum sau tsib 3d orbitals feem ntau ua rau tag nrho cov hluav taws xob poob qis thiab nce hauv electronegativity ntawm cov ntsiab lus. Arsenic nyob rau hauv lub sij hawm lub sij hawm yuav muab piv nrog rau lwm cov pab pawg neeg uas qhia kom meej qhov qauv no. Piv txwv li, nws feem ntau lees txais tias zinc yogntau electronegative tshaj magnesium thiab gallium tshaj txhuas. Txawm li cas los xij, hauv cov pab pawg tom ntej, qhov sib txawv no nqaim, thiab ntau qhov tsis pom zoo tias germanium yog electronegative ntau dua li silicon, txawm tias muaj ntau cov pov thawj tshuaj. Ib qho kev hloov pauv zoo sib xws los ntawm 8- mus rau 18-lub plhaub ntawm phosphorus mus rau arsenic tuaj yeem ua rau cov electronegativity, tab sis qhov no tseem muaj teeb meem.
Qhov zoo sib xws ntawm lub plhaub sab nrauv ntawm As thiab P qhia tias lawv tuaj yeem tsim 3 covalent daim ntawv cog lus rau ib lub atom nyob rau hauv lub xub ntiag ntawm ib tug ntxiv unbonded electron khub. Yog li ntawd, lub xeev oxidation yuav tsum yog +3 lossis -3, nyob ntawm seb qhov sib txheeb ntawm electronegativity. Cov qauv ntawm arsenic kuj hais txog qhov muaj peev xwm ntawm kev siv sab nrauv d-orbital los nthuav cov octet, uas tso cai rau lub caij los ua 5 daim ntawv cog lus. Nws tsuas yog pom tau los ntawm cov tshuaj tiv thaiv nrog fluorine. Lub xub ntiag ntawm ib tug dawb electron khub rau kev tsim ntawm complex compounds (los ntawm electron pub dawb) nyob rau hauv lub As atom yog npaum li cas tsawg pronounced tshaj nyob rau hauv phosphorus thiab nitrogen.
Arsenic ruaj khov hauv huab cua qhuav, tab sis hauv huab cua ntub nws dhau los ua cov oxide dub. Nws vapor hlawv yooj yim, tsim As2O3. Dab tsi yog dawb arsenic? Nws yog xyaum tsis cuam tshuam los ntawm dej, alkalis thiab non-oxidizing acids, tab sis yog oxidized los ntawm nitric acid mus rau lub xeev ntawm +5. Halogens, sulfur reacts nrog arsenic, thiab ntau cov hlau tsim arsenides.
tshuaj ntsuam chemistry
Cov tshuaj arsenic tuaj yeem kuaj pom tau zoo raws li cov kab daj daj uas ua rau muaj kev cuam tshuam ntawm 25%hydrochloric acid daws. Cov kab ntawm Raws li feem ntau txiav txim siab los ntawm kev hloov nws mus rau arsine, uas tuaj yeem kuaj pom siv Marsh test. Arsine thermally decomposes, tsim ib daim iav dub arsenic hauv lub raj nqaim. Raws li txoj kev Gutzeit, kev sojntsuam impregnated nrog mercury chloride, nyob rau hauv lub zog ntawm arsine, darkens vim tso tawm mercury.
toxicological yam ntxwv ntawm arsenic
Cov tshuaj toxicity ntawm lub caij thiab nws cov derivatives sib txawv nyob rau hauv ntau yam, los ntawm cov tshuaj lom arsine thiab nws cov organic derivatives mus rau yooj yim li, uas yog inert heev. Kev siv nws cov organic tebchaw ua tshuaj tua rog (lewisite), vesicant thiab defoliant (Agent Blue raws li cov dej sib xyaw ntawm 5% cacodylic acid thiab 26% ntawm nws cov ntsev ntsev) qhia peb tias arsenic yog dab tsi.
Feem ntau, cov khoom siv ntawm cov tshuaj no ua rau tawv nqaij thiab ua rau dermatitis. Kev nqus pa tiv thaiv cov plua plav uas muaj arsenic kuj tau pom zoo, tab sis feem ntau cov tshuaj lom tshwm sim thaum nws noj. Qhov siab tshaj plaws tso cai pom zoo ntawm Raws li hauv plua plav rau yim teev ua haujlwm hnub yog 0.5 mg / m3. Rau arsine, koob tshuaj txo qis rau 0.05 ppm. Ntxiv nrog rau kev siv cov tshuaj sib xyaw ua ke ntawm cov tshuaj no ua tshuaj tua kab thiab tshuaj tua kab, kev siv arsenic hauv chaw muag tshuaj tau ua kom tau txais salvarsan, thawj cov tshuaj tiv thaiv kab mob syphilis.
He alth teebmeem
Arsenic yog ib qho ntawm cov tshuaj lom ntau tshaj plaws. Inorganic compounds ntawm ib tug muab tshuajCov tshuaj ib txwm tshwm sim hauv qhov me me. Tib neeg tuaj yeem raug arsenic los ntawm zaub mov, dej, thiab huab cua. Kev kis tau tuaj yeem tshwm sim los ntawm kev sib cuag ntawm daim tawv nqaij nrog cov av tsis huv lossis dej.
Cov ntsiab lus ntawm arsenic hauv zaub mov yog tsawg heev. Txawm li cas los xij, qib hauv cov ntses thiab nqaij nruab deg tuaj yeem siab heev vim lawv nqus cov tshuaj los ntawm cov dej uas lawv nyob hauv. Qhov tseem ceeb ntawm inorganic arsenic hauv cov ntses tuaj yeem ua rau muaj kev pheej hmoo rau tib neeg kev noj qab haus huv.
Cov neeg ua haujlwm nrog cov tshuaj, nyob hauv tsev tsim los ntawm ntoo kho nrog nws, thiab hauv thaj av ua liaj ua teb uas tau siv tshuaj tua kab yav dhau los kuj raug tshuaj.
Inorganic arsenic tuaj yeem ua rau ntau yam teebmeem kev noj qab haus huv hauv tib neeg, xws li plab thiab plab hnyuv, txo qis cov qe ntshav liab thiab dawb, hloov ntawm daim tawv nqaij, thiab mob ntsws. Nws ntseeg tau tias kev noj cov tshuaj no ntau ntxiv tuaj yeem ua rau muaj feem mob qog noj ntshav, tshwj xeeb tshaj yog ntawm daim tawv nqaij, ntsws, daim siab, thiab qog nqaij hlav qog nqaij hlav cancer.
Cov ntsiab lus siab ntawm inorganic arsenic ua rau muaj menyuam tsis taus thiab nchuav menyuam hauv cov poj niam, dermatitis, txo qis tiv thaiv kab mob, teeb meem plawv thiab hlwb puas. Tsis tas li ntawd, cov tshuaj no tuaj yeem ua rau DNA puas.
koob tshuaj dawb ntawm arsenic yog 100 mg.
Cov tshuaj organic ntawm lub caij tsis ua rau mob qog noj ntshav lossis kev puas tsuaj rau cov caj ces, tab sis cov koob tshuaj ntau tuaj yeemua rau tib neeg noj qab haus huv, xws li ua rau mob hlab ntsha tawg lossis mob plab.
Properties As
Cov tshuaj tseem ceeb thiab lub cev ntawm arsenic yog raws li hauv qab no:
- Atomic naj npawb - 33.
- Atomic hnyav yog 74.9216.
- Lub melting point ntawm cov pwm grey yog 814 ° C ntawm lub siab ntawm 36 atmospheres.
- Grey Density 5.73g/cm3 at 14°C.
- Yellow pwm ntom 2.03 g / cm 3 ntawm 18 ° C.
- Cov mis hluav taws xob ntawm arsenic yog 1s22s22p63s 23p63d104s24p 33
- Oxidation xeev - -3, +3, +5.
- Arsenic valency yog 3, 5.
