Lub ntsiab lus sib txawv ntawm graphite thiab cov hmoov txhuas yog tias graphite yog nontoxic thiab khov khov, hos txhuas yog kuab lom thiab tsis ruaj khov.
Graphite graphite yog dab tsi?
Graphite yog ib feem ntawm carbon muaj kev ruaj khov, crystalline qauv. Nws yog daim ntawv ntawm cov thee. Tsis tas li ntawd, nws yog ib txwm ntxhia. Cov zaub mov ib txwm muaj cov tshuaj muaj ib qho tshuaj lom neeg uas tshwm sim hauv qhov tsis muaj lwm yam khoom. Ntxiv mus, graphite yog cov qauv uas tseem ceeb tshaj plaws uas tshwm sim ntawm cov ntsuas kub thiab siab. Qhov rov qab ua dua ntawm graphite faib yog carbon (c). Graphite muaj hexagonal crystal system. Nws tshwm nyob rau hauv ib tug hlau-dub rau steel-grey xim thiab kuj muaj xim hlau luster. Lub streak xim ntawm graphite yog xim dub (xim ntawm cov hmoov nplej siab (ntxhia).
Cov qauv siv lead ua ib qho muaj cov honeycomb kaum. Nws muaj graphene cov ntawv sib cais ntawm 0.335 nm nrug. Hauv cov qauv ntawm cov qauv ntawm graphite, qhov deb ntawm cov pa roj carbon atoms yog 0.142 nm. Cov pa roj carbon atoms khi rau txhua lwm yam ntawm kev sib tsooalent, ib qho carbon atom muaj peb txoj kev sib tsoo ib txwm nyob ib puag ncig nws. Qhov tseem ceeb ntawm cov pa roj carbon atom yog 4; Yog li, muaj plaub unoccupied electron hauv txhua thiab txhua tus pa roj ntawm cov qauv no. Yog li ntawd, cov tshuab hluav taws xob no yog pub dawb rau tsiv chaw, ua graphite hluav taws xob coj. Ntuj graphite yog pab tau nyob rau hauv refractories, roj teeb, steelmaking, nthuav graphite, foundry ntsib, thiab lubricants thiab roj nplua nyeem.
Hmoov txhuas yog dab tsi?
Hmoov txhuas yog tshuaj lom neeg muaj cov tshuaj atomic naj npawb 82 thiab cov tshuaj lom neeg lub cim pb. Nws tshwm sim ua cov hlau me me tshuaj. Cov hlau no yog cov hlau hnyav thiab yog denser dua feem ntau ntawm cov ntaub ntawv uas peb paub. Tsis tas li ntawd, txhuas tuaj yeem tshwm sim raws li cov hlau muag muag thiab malleable hlau muaj lub ntsej muag tsawg. Peb tuaj yeem yooj yim txiav cov hlau no, thiab nws muaj cov kab mob xiav xiav nrog rau Silvery Grey Metallic tsos Tseem ceeb tshaj, cov hlau no muaj cov atomic siab tshaj plaws ntawm ib qho chaw ruaj khov.
Thaum xaiv cov khoom ntawm cov txhuas, nws muaj qhov ntom ntom, malleability, ductility, thiab siab rau corrosion vim tias passivation. Lead muaj lub ntsej muag kaw lub ntsej muag sib ze thiab qhov hnyav atomic hnyav, uas yog ntau dua li cov hlau xws li hlau, tooj liab, thiab zinc. Thaum piv rau feem ntau cov hlau, txhuas muaj qhov tsis tshua muaj suab, thiab nws qhov cub npau npau yog tseem qis dua ntawm pab pawg 14 cov ntsiab lus.
Leads ua cov txheej tiv thaiv kom tsis txhob muaj huab cua. Feem ntau ib txwm muaj nyob ntawm no txheej yog txhuas (II) carbonate. Nws tseem tuaj yeem yog cov sulfate thiab chloride cheeb tsam ntawm cov hmoov txhuas. Cov txheej no ua rau cov hmoov txhuas saum npoo hlau inert rau huab cua. Tsis tas li ntawd, cov tshuaj fluorine tuaj yeem ua rau muaj kev coj noj coj ua nrog rau chav sov kom tsim txhuas (II) cov tshuaj fluoride. Muaj cov tshuaj tiv thaiv zoo sib xws nrog cov tshuaj chlorine zoo li, tab sis nws yuav tsum tau cua sov. Sib nrug los ntawm qhov ntawd, txhuas hlau yog resistant rau sulfuric acid thiab phosphoric acid tab sis reacts nrog hcL thiab hno3 acid. Organic acids xws li acetic acid tuaj yeem tshem tawm cov kev coj ua nyob rau hauv muaj cov pa oxygen. Ib yam li ntawd, factrrated alkali acids tuaj yeem yaj ua rau daim ntawv plumbites.
Txij li txhuas tau outlawed nyob rau hauv teb chaws USA xyoo 1978 raws li ib qho khoom xyaw hauv cov xim vim muaj kuab lom, nws tsis yog siv rau kev tsim lub xaum. Txawm li cas los xij, nws yog cov khoom siv tseem ceeb siv rau mem hluav tsim ua ntej lub sijhawm ntawd. Cov hmoov txhuas tau raug lees paub tias yog cov tshuaj lom heev rau tib neeg. Yog li ntawd, tib neeg nrhiav rau cov khoom hloov pauv cov kev coj ua nrog lwm yam los tsim cov xaum qhuav.
Dab tsi yog qhov sib txawv ntawm graphite thiab cov hmoov txhuas?
Graphite thiab txhuas yog cov tshuaj tseem ceeb vim lawv cov khoom muaj txiaj ntsig thiab cov ntawv thov. Lub ntsiab lus sib txawv ntawm graphite thiab cov hmoov txhuas yog tias graphite yog nontoxic thiab khov khov, hos txhuas yog kuab lom thiab tsis ruaj khov.
Hmoov txhuas yog qhov cuam tshuam tsis tau ntawm kev hloov pauv tom qab. Peb tuaj yeem ua piv txwv cov tsis muaj zog yog xim hlau tus cwj pwm ntawm cov txhuas siv nws cov amphoteric xwm. Piv txwv li Lead thiab Lead Oxides tshwm sim nrog cov kua qaub thiab cov hauv paus thiab zoo li yuav ua kev sib haum cua. Tebchaw ntawm cov hmoov txhuas feem ntau muaj +2 oxidation xeev txhuas es tsis yog +4 oxidation xeev (+4 yog feem ntau cov oxidation rau pab pawg 14 cov ntsiab lus).
Lub Sijhawm Post: Jul-08-2022
