Yuav ua li cas yog arsenic? Nta, lub zog thiab daim ntaub ntawv

Arsenic - tshuaj caij nitrogen pab pawg neeg (Group 15 ntawm periodic rooj). Qhov no gray nws yog xim hlau ci nkig tshuaj (α-arsenic) nrog ib tug rhombohedral siv lead ua ntxaij ntoo. Thaum rhuab mus 600 ° C Raws li sublimates. Thaum cua txias, ib tug vapor, ib tug tshiab hloov - Daj arsenic. Saum toj no 270 ° C rau tag nrho cov Raws li tsiv mus rau hauv lub dub arsenic.

Keeb kwm ntawm foundations

Lub fact tias qhov no arsenic twb paub ntev ua ntej cov paub txog nws cov tshuaj hais. Lub IV c. BC. e. Aristotle hais txog ib yam khoom uas hu ua "sandarak", uas yog tam sim no ntseeg tau tias muaj tau realgar, los yog arsenic sulfide. Thiab nyob rau hauv lub xyoo pua kuv BC. e. Pliniy Starshy thiab sau ntawv Pedany Dioscoride piav auripigment - zas Raws li ₂ S _3. Nyob rau hauv XI nyob rau hauv. n. e. differed peb ntau ntau yam "arsenic" dawb (Raws li ₄ O _6), daj (Raws li ₂ S _3), thiab liab (Raws li ₄ S _4). Cov khoom nws tus kheej tej zaum twb thawj cais nyob rau hauv lub XIII xyoo pua, Albert lub Great, uas sau tseg cov tsos ntawm cov hlau-zoo li tshuaj yeeb dej caw thaum Ars, kuj hu ua li ₂ S ₃ yog rhuab nrog xab npum thiab dej. Tab sis cog qoob loo nyob rau hauv lub fact tias lub ntuj paub txog yog ntshiab arsenic, tsis muaj. Tus thawj tiag tiag pov thawj ntawm cov nyiaj ntawm ntshiab tshuaj caij yog sau hnub tim rau 1649. German tus kws muab tshuaj Iogann Shreder npaj arsenic, cua sov nws nyob rau hauv lub xub ntiag ntawm cov pa roj carbon monoxide. Tom qab ntawd Nicolas Lemery, Fabkis tus kws kho mob thiab kws tshuaj pom tus tsim ntawm no tshuaj caij los ntawm cua sov ib tug sib tov ntawm ib tug oxide, thiab potash soaps. By pib ntawm XVIII xyoo pua, arsenic yog twb paub raws li ib tug cim semi-hlau.

loj heev

Lub ntiaj teb ua kiav txhab thiab yog tsis muaj arsenic concentration yog 1.5 ppm. Nws yog pom nyob rau hauv cov av thiab cov zaub mov thiab tej zaum yuav nkag tau rau hauv cov huab cua, dej thiab av vim cua thiab dej yaig. Tsis tas li ntawd, lub caij nkag mus rau hauv cov cua los ntawm lwm qhov chaw. Raws li ib tug tshwm sim ntawm volcanic eruptions nyob rau hauv cov huab cua yog tso tawm hais txog 3 txhiab. T arsenic hauv ib xyoos, kab mob tsim 20 txhiab. T volatile metilarsina ib xyoo, thiab raws li ib tug tshwm sim ntawm burning fossil fuels nyob rau hauv tib lub sij hawm yog faib 80 txhiab. T.

Txawm tias muaj tseeb hais tias cov Raws li - ib cov tshuaj lom, nws yog ib qho tseem ceeb feem ntawm lub hwj chim ntawm ib co tsiaj txhu thiab tejzaum nws tib neeg, txawm hais tias tus tsim nyog koob tshuaj tsis pub tshaj 0.01 mg / hnub.

Arsenic yog tsis tshua muaj yooj yim txhais mus rau hauv ib tug dej-soluble los yog volatile lub xeev. Lub fact tias nws yog heev mobile, txhais tau tias ib tug loj concentration ntawm cov tshuaj yeeb dej caw nyob rau hauv ib tug qhov chaw yuav tuaj tsis tau. Nyob rau hauv ib tes, qhov no yog zoo, tab sis nyob rau lwm yam - qhov yooj yim uas nws kis, yog vim li cas hais tias cov arsenic paug yog ua ib tug loj teeb meem. Vim tib neeg kev ua ub no, mas los ntawm tsuas thiab melting, feem ntau tsis tshais tshuaj caij migrates, thiab tam sim no nws muaj peev xwm yuav nrhiav tau tsis tsuas nyob rau hauv lub qhov chaw ntawm lub ntuj concentration.

Tus nqi ntawm cov arsenic nyob rau hauv lub kiav txhab yog kwv yees li 5 g ib ton. Nyob rau hauv qhov chaw, nws yog kwv yees li lub concentration ntawm 4 atoms ntawm ib lab silicon atoms. Qhov no lub caij yog dav faib. Ib tug me me npaum li cas yog tam sim no nyob rau hauv cov neeg lub xeev. Feem ntau, tus tsim ntawm 90-98% purity arsenic tshwm sim ua ke nrog co xws li antimony thiab nyiaj. Feem ntau ntawm nws, txawm li cas los, yog ib feem ntawm ntau tshaj 150 txawv minerals - sulphides, arsenides, sulphoarsenides thiab arsenite. Arsenopyrite FeAsS yog ib qho ntawm feem ntau Raws li-kev coj tus kheej cov zaub mov. Lwm yam common arsenic tebchaw - minerals realgar Raws li ₄ S _4, auripigment Raws li ₂ S _3, loellingite FeAs thiab enargite ₂ Cu ₃ lub nroog Yeiuxalees _4. Tsis tas li ntawd ntau arsenic oxide. Feem ntau ntawm cov khoom no yog ib tug byproduct ntawm lub smelting ntawm tooj liab, hmoov txhuas, cobalt, thiab kub ores.

Nyob rau hauv cov xwm, muaj no tsuas muaj ib ruaj khov isotope ntawm arsenic - ⁷⁵ Raws li. Cov khoom cua tej isotopes tso ⁷⁶ Raws li c ib nrab-lub neej ntawm 26,4 teev. Arsenic-72, -74 thiab -76 yog siv nyob rau hauv kev kho mob diagnostics.

Muaj ntau lawm thiab kev siv

Hlau arsenic arsenopyrite npaj los ntawm cua kub los 650-700 ° C tsis muaj kev nkag ntawm huab cua. Yog hais tias arsenopyrite thiab lwm yam hlau ores rhuab nrog rau oxygen, cov Raws li yooj yim reacts nrog lawv nyob rau hauv compound daim ntawv nkag sublimes Raws li ₄ O _6, kuj hu ua "dawb arsenic". oxide vapors tau sau thiab condensed, thiab tom qab rov lim los ntawm sublimation. Feem ntau cov Raws li nws yog ua los ntawm cov pa roj carbon yuav txo tau ntawm dawb arsenic li tau.

Ntiaj teb tau ntawm nws yog xim hlau arsenic yog tus me me - tsuas yog ib ob peb puas tons ib xyoos twg. Ntau yam uas yog noj, los ntawm Sweden. Nws yog siv nyob rau hauv metallurgy vim hais tias ntawm nws cov metalloid zog. Hais txog 1% ntawm cov arsenic yog siv nyob rau hauv qhov siv thiab ua cov hlau lead txhaj koob tshuaj tivthaiv, raws li nws pab txoj kev roundness ntawm lub molten mob. Lub zog ntawm cov kabmob hlau raws li nyob rau hauv cov hlau lead yog zoo ob nyob rau hauv lub thermal thiab txhua yam ntxwv ntawm thaum lawv muaj txog 3% ntawm arsenic. Lub xub ntiag ntawm me me ntawm no tshuaj caij nyob rau hauv cov hlau lead alloys tempers lawv siv nyob rau hauv roj teeb thiab lub cable armor. Me impurities yog arsenic nce xeb kuj thiab thermal thaj chaw ntawm tooj liab thiab tooj dag. Cov ntshiab elemental tshuaj Raws li bronze yog siv rau kev thov coatings thiab nyob rau hauv pyrotechnics. Heev arsenic pom daim ntawv thov nyob rau hauv semiconductor technology, qhov twg nws yog siv nrog silicon thiab germanium, raws li zoo raws li nyob rau hauv daim ntawv ntawm cov gallium arsenide (GaAs) nyob rau hauv lub diodes, lasers thiab transistors.

Raws li tebchaw

Txij li thaum arsenic valence yog 3 thiab 5, thiab nws muaj ob peb oxidation lub xeev los ntawm -3 mus +5, lub caij tej zaum yuav tsim ntau hom tebchaw. Qhov tseem ceeb tshaj coj mus muag tseem ceeb nws oxides, yooj yim ntaub ntawv ntawm cov uas yog cov ₄ O ₆ thiab Raws li ₂ O _5. Arsenous oxide, feem ntau hu ua dawb arsenic, - ib tug byproduct ci ores ntawm tooj liab, hlau thiab ib co lwm yam co, raws li zoo raws li sulfide ores thiab arsenopyrite. Nws yog tus pib cov ntaub ntawv uas rau feem ntau ntawm cov lwm tebchaw. Nyob rau hauv tas li ntawd, nws yog siv nyob rau hauv cov tshuaj tua kab, siv decolorizing neeg sawv cev nyob rau hauv lub chaw ua khoom ntawm lub khob thiab preservative rau tawv. arsenic pentoxide yog tsim thaum nphav raug cov oxidant (e.g., nitric acid) mus dawb arsenic. Nws yog qhov tseem ceeb muaj ntawm tshuaj tua kab, herbicides thiab cov nplaum rau cov hlau.

Arsine (tshauv _3), tshuaj lom tsis muaj kob roj muaj hydrogen thiab arsenic, - yog lwm lub npe hu substance. Cov tshuaj yeeb dej caw, kuj hu ua arsenical hydrogen yog npaj los ntawm hydrolysis ntawm hlau arsenides, thiab hlau rov qab los ntawm arsenic tebchaw nyob rau hauv acid daws teeb meem. Nws tau pom daim ntawv thov raws li ib tug dopant nyob rau hauv semiconductors thiab cov tub rog tshuaj lom roj. Nyob rau hauv ua liaj ua teb, tseem ceeb heev arsenic acid (H ₃ ua _4), ua arsenate (PbHAsO ₄₎ thiab calcium arsenate [Ca ₃ (ua _{4) 2],} uas yog siv los ntxuav cov av thiab cov kab no.

Arsenic - tshuaj caij txoj kev ua ib plurality ntawm organic tebchaw. Kakodin (CH _{3) 2} Raws li-Raws li _{(CH3) 2,} piv txwv li, siv nyob rau hauv qhov kev npaj ntawm ib tug yawm lug siv desiccant (kom qhuav sawv cev) - cacodylic acid. Complex organic compound ntawm lub caij siv nyob rau hauv cov kev kho mob ntawm tej yam kab mob xws li amoebic dysentery tshwm sim los ntawm microorganisms.

lub zog

Yuav ua li cas yog arsenic nyob rau hauv cov nqe lus ntawm nws lub zog? Nyob rau hauv nws cov feem ntau ruaj khov lub xeev, nws yog ib tug nkig khoom steel gray xim nrog tsawg cua sov thiab hluav taws xob conductivity. Txawm tias ib co ntaub ntawv uas li yog hlau-li, nws txoj hauj lwm uas tsis yog-hlau - ib tug ntau yog characterization ntawm arsenic. Nws muaj lwm yam hom arsenic, tab sis lawv tsis zoo heev kawm, tshwj xeeb tshaj yog daj metastable daim ntawv, muaj raws ntawm molecules Raws li _4, zoo li dawb phosphorus P _4. Arsenic sublimes ntawm ib tug kub ntawm 613 ° C, thiab raws li ib tug pa tshwm sim raws li molecules Raws li _4, uas tsis dissociate mus rau ib tug kub ntawm txog 800 ° C. Sau kom tiav dissociation ntawm molecules nyob rau Raws li ₂ yuav siv sij hawm qhov chaw nyob rau 1700 ° C.

Atomic qauv thiab muaj peev xwm mus tsim bonds

Hauv arsenic mis - 1s ² 2s ² 2p ⁶ 3s ² 3p ⁶ 3d ¹⁰ 4s ² 4p ^{3 -} zoo li nitrogen thiab phosphorus uas muaj tsib electrons nyob rau hauv lub plhaub, tab sis nws txawv ntawm lawv nyob rau hauv lub xub ntiag ntawm 18 electrons nyob rau hauv lub penultimate plhaub es tsis txhob ntawm ob los yog yim. Tsis tas li ntawd ntawm 10 zoo nqi nyob rau hauv cov tub ntxhais thaum lub sij hawm sau tsib 3d-orbitals feem ntau ua rau cov kev txo ntawm lub electron huab thiab ua electronegativity ntsiab. Arsenic nyob rau hauv lub periodic rooj yuav muab piv nrog rau lwm cov pab pawg, uas kom meej meej qhia no txawv. Piv txwv li, nws yog feem ntau txais tias zinc yog ntau electronegative tshaj magnesium thiab gallium - tshaj txhuas. Txawm li cas los, nyob rau hauv cov nram no pab pawg neeg, qhov no txawv dua li qub, thiab muaj ntau yam tsis pom zoo nrog lub fact tias lub teb chaws Yelemees electronegativity ntawm pob zeb ntais, txawm lub nplua mais ntawm cov tshuaj pov thawj. Qhov no txoj kev hloov los ntawm 8-mus rau 18-cell daim nyias nyias los ntawm phosphorus rau arsenic yuav ua rau kom lub electronegativity, tab sis nws tseem muaj teeb meem.

Kev zoo sib thooj li cov txheej plhaub thiab P ntawd hais tias lawv muaj peev xwm tsim peb covalent bonds ib atom nyob rau hauv lub xub ntiag ntawm ntxiv unbound electron khub. Cov oxidation yuav tsum yog li ntawd yuav +3 los yog -3, nyob ntawm seb lub kev sib nrig sib txheeb ze electronegativity. Tus qauv ntawm arsenic kuj qhia tau ntawm kev siv ib tug sab nraud d-orbitals rau lub expansion ntawm lub octet uas tso cai rau lub caij mus ua ib lub 5 ties. Nws yog pom tau hais xwb nyob rau hauv cov tshuaj tiv thaiv nrog fluorine. Qhov kuaj pom ntawm ib tug dawb electron khub rau cov tsim ntawm complex tebchaw (ntawm electron pub dawb) Raws li nyob rau hauv atom tshwm ntau npaum li cas me dua cov phosphorus thiab nitrogen.

Arsenic yog ruaj khov nyob rau hauv qhuav huab cua, tiam sis nyob rau hauv noo them nrog dub oxide. Nws vapors yog combusted yooj yim tsim Raws li ₂ O _3. Yuav ua li cas yog arsenic nyob rau hauv lub dawb lub xeev? Nws yog suab tsis raug rau cov dej, alkalis thiab uas tsis yog-oxidizing acids, tab sis yog oxidized nrog nitric acid mus rau ib tug lub xeev +5. Txij li thaum arsenic hnov mob halogens, sulfur, thiab ntau co ntawv arsenides.

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Cov tshuaj yeeb dej caw yuav raug kuaj qualitatively arsenic raws li ib tug daj orpiment precipitates nyob rau hauv qhov kev txiav txim ntawm 25% hydrochloric acid tshuaj. Ib co kua nplaum uas li, feem ntau yog txiav txim los ntawm nws hloov dua siab tshiab rau arsine, uas muaj peev xwm yuav ntes tau los ntawm lub peb hlis ntuj mus kuaj. Arsine yog thermally decomposed mus ua ib lub dub daim iav ntawm arsenic nyob rau hauv lub nqaim raj. Los ntawm txoj kev Gutzeit sojntsuam impregnated nrog mercury chloride nyob rau hauv qhov kev txiav txim ntawm arsine tsaus vim nag lossis daus ntawm mercury.

arsenic toxicological yam ntxwv

cell toxicity thiab nws cov derivatives yog lug txawv nyob rau hauv ib ntau yam, los ntawm tsis tshua muaj neeg lom arsine thiab nws cov organic derivatives cias Raws li, uas yog tus inert. Lub fact tias xws li arsenic, hais tias kev siv ntawm nws cov organic tebchaw raws li ib tug tshuaj rog cov neeg ua hauj (lewisite), sawv hlwv neeg saib xyuas thiab defoliant ( "Tus neeg saib xyuas xiav" raws li ib tug aqueous sib tov ntawm 5% cacodylic acid 26% ntawm nws cov sodium ntsev).

Nyob rau hauv kev, derivatives ntawm no tshuaj caij chim siab ntawm daim tawv nqaij thiab ua rau dermatitis. Tsis tas li ntawd pom zoo kev pab tiv thaiv los ntawm nqus tau pa ntawm arsenic uas muaj hmoov av, tiam sis feem ntau lom tshwm sim thaum noj. Maximum permissible concentration ntawm Raws li nyob rau hauv cov hmoov av ib yim-teev ib hnub yog 0.5 mg / m ^3. Rau arsine koob tshuaj yog txo mus rau 0.05 qhov chaw rau ib lab. Dhau li ntawm tus siv ntawm lub tebchaw ntawm cov tshuaj caij li herbicides thiab cov tshuaj tua kab, arsenic daim ntawv thov nyob rau hauv pharmacology yielded salvarsan - thawj kev vam meej tshuaj tiv thaiv syphilis.

Rau kev kho mob

Arsenic yog ib qho ntawm feem lom ntsiab. Inorganic sib txuas ntawm cov tshuaj pom lawm nyob rau hauv me me nyiaj. Cov neeg siv tej zaum yuav tsum tau raug mus arsenic los ntawm cov zaub mov, dej thiab huab cua. Raug tej zaum kuj tshwm sim raws li qhov hu ntawm daim tawv nqaij nrog cov zaub mov av los yog dej.

lub arsenic cov ntsiab lus yog heev tsawg nyob rau hauv cov zaub mov. Txawm li cas los, nws theem nyob rau hauv ntses thiab qwj ntses kuj yuav ua tau heev, txij li thaum lawv nqus tshuaj active keeb ntawm cov dej nyob rau hauv uas lawv nyob. Ib tug tseem ceeb npaum li cas ntawm inorganic arsenic nyob rau hauv cov ntses tej zaum yuav ua tau ib tug teeb meem rau tib neeg noj qab haus huv.

Cov teebmeem ntawm tshuaj yog tseem raug rau cov neeg uas ua hauj lwm nrog lawv, nyob rau hauv lub tsev ua ntawm ntoo kho nrog lawv, thiab nyob rau ua liaj ua teb av, uas nyob rau hauv lub dhau los lawm siv cov tshuaj tua kab.

Inorganic arsenic yuav ua rau ntau yam kev kho mob los xws li voos ntawm lub plab thiab cov hnyuv, tsis ntau lawm ntawm liab thiab dawb ntshav hlwb, daim tawv nqaij hloov, thiab mob ntsws voos. Nws yog assumed tias tus haum ntawm ib tug tseem ceeb npaum li cas ntawm qhov no tshuaj yuav ua rau kom qhov uas yuav muaj mob cancer, tshwj xeeb tshaj yog cov tawv nqaij cancer, mob ntsws, kab mob siab thiab lymphatic system.

Heev END ntawm inorganic arsenic yog qhov ua rau ntawm ntxiv lawm tshob thiab nchuav menyuam ntawm cov pojniam, dermatitis, tej kuj mus kab mob, lub plawv muaj teeb meem thiab puas hlwb. Tsis tas li ntawd, qhov no tshuaj caij muaj peev xwm sawv ntawm ua DNA.

Tuag koob tshuaj dawb arsenic yog 100 mg.

Cov organic compound ntawm ib tug caij los yog mob cancer, los yog puas lub caj code tsis ua, tab sis siab koob tshuaj yuav ua mob tau rau tib neeg noj qab haus huv, xws li yuav ua tau kom tshee ntshawv siab los yog mob nyob rau hauv lub plab mog.

Raws li cov khoom

Basic tshuaj thiab lub cev thaj chaw ntawm arsenic nram qab no:

• Atomic tooj - 33.
• Atomic hnyav - 74,9216.
• Melting point gray pwm - 814 ° C rau ib lub siab ntawm 36 atmospheres.
• Ceev gray pwm - 5,73 g / cm ³ ntawm 14 ° C.
• Cov kev ceev ntawm lub daj daim ntawv - 2,03 g / cm ³ rau ntawm 18 ° C.
• Hauv arsenic mis - 1s 2s ^{2 2 2} 2p ⁶ 3s 3p ⁶ 3d ¹⁰ 4s ² 4p _^3.
• oxidation lub xeev - -3, +3, +5.
• Valency ntawm arsenic - 3, 5.