Dab tsi yog qhov txawv ntawm Graphite thiab Lead Lub Xya Hli?

Qhov sib txawv tseem ceeb ntawm graphite thiab txhuas yog tias graphite yog nontoxic thiab ruaj khov heev, whereas lead yog lom thiab tsis ruaj khov.

Graphite yog dab tsi?

Graphite yog ib qho allotrope ntawm cov pa roj carbon uas muaj qhov ruaj khov, crystalline qauv.Nws yog ib daim ntawv ntawm cov thee.Tsis tas li ntawd, nws yog ib haiv neeg ntxhia.Native minerals yog cov khoom uas muaj ib qho tshuaj lom neeg uas tshwm sim hauv qhov tsis muaj kev sib txuas nrog lwm cov khoom.Ntxiv mus, graphite yog daim ntawv ruaj khov tshaj plaws ntawm carbon uas tshwm sim ntawm tus qauv kub thiab siab.Qhov rov ua dua ntawm graphite allotrope yog carbon (C).Graphite muaj hexagonal siv lead ua system.Nws tshwm nyob rau hauv ib tug hlau-dub mus rau steel-grey xim thiab kuj muaj ib tug metallic lustre.Cov xim streak ntawm graphite yog dub (xim ntawm cov hmoov ntxhia zoo).

Lub graphite siv lead ua qauv muaj ib tug honeycomb lattice.Nws muaj cov nplooj ntawv graphene sib cais ntawm 0.335 nm nrug.Hauv cov qauv ntawm graphite, qhov kev ncua deb ntawm carbon atoms yog 0.142 nm.Cov pa roj carbon atoms khi rau ib leeg ntawm covalent bonds, ib qho carbon atom muaj peb covalent bonds nyob ib ncig ntawm nws.Lub valency ntawm carbon atom yog 4;Yog li, muaj plaub yam tsis muaj hluav taws xob nyob rau hauv txhua thiab txhua txhua carbon atom ntawm cov qauv no.Yog li ntawd, qhov no electron yog dawb mus tsiv teb tsaws, ua graphite hluav taws xob conductive.Ntuj graphite yog pab tau nyob rau hauv refractories, roj teeb, steelmaking, nthuav graphite, nres linings, foundry ntsib, thiab lubricants.

Lead yog dab tsi?

Lead yog cov khoom siv tshuaj muaj atomic tooj 82 thiab cov cim tshuaj Pb.Nws tshwm sim raws li cov tshuaj lom neeg hlau.Cov hlau no yog cov hlau hnyav thiab hnyav dua li feem ntau ntawm cov ntaub ntawv uas peb paub.Tsis tas li ntawd, txhuas tuaj yeem tshwm sim raws li cov hlau mos thiab malleable uas muaj cov ntsiab lus melting tsawg.Peb tuaj yeem txiav cov hlau no yooj yim, thiab nws muaj cov yam ntxwv xiav hint nrog rau cov xim silvery grey metallic tsos.Qhov tseem ceeb tshaj, cov hlau no muaj tus lej atomic ntau tshaj plaws ntawm cov khoom ruaj khov.

Thaum xaiv cov khoom ntawm cov txhuas, nws muaj qhov ntom ntom, malleability, ductility, thiab siab rau corrosion vim tias passivation.Cov hmoov txhuas muaj lub ntsej muag zoo sib xws hauv cov qauv cubic thiab qhov hnyav atomic, uas ua rau muaj qhov ntom ntom ntom ntom ntom ntom ntawm cov hlau feem ntau xws li hlau, tooj liab, thiab zinc.Thaum piv rau feem ntau cov hlau, txhuas muaj qhov melting point tsawg heev, thiab nws cov boiling point kuj yog qhov qis tshaj ntawm pawg 14 ntsiab.

Lead nyiam tsim ib txheej tiv thaiv thaum raug huab cua.Qhov feem ntau cov ntsiab lus ntawm cov txheej no yog lead (II) carbonate.Kuj tseem tuaj yeem muaj sulfate thiab chloride Cheebtsam ntawm cov hlau lead.Cov txheej no ua rau cov hlau lead saum npoo zoo chemically inert rau huab cua.Tsis tas li ntawd, cov roj fluorine tuaj yeem hnov ​​​​mob nrog cov hmoov txhuas hauv chav tsev kub kom tsim tau cov hmoov lead (II) fluoride.Muaj cov tshuaj tiv thaiv zoo sib xws nrog cov roj chlorine, tab sis nws yuav tsum tau cua sov.Tsis tas li ntawd, cov hlau lead yog resistant rau sulfuric acid thiab phosphoric acid tab sis reacts nrog HCl thiab HNO3 acid.Organic acids xws li acetic acid tuaj yeem yaj cov hlau lead hauv lub xub ntiag ntawm oxygen.Ib yam li ntawd, concentrated alkali acids tuaj yeem yaj ua rau cov plumbites.

Txij li cov hlau lead tau raug cai nyob rau hauv Teb Chaws Asmeskas xyoo 1978 raws li cov khoom xyaw hauv cov xim vim muaj kev phom sij, nws tsis tau siv rau cov xaum qhuav.Txawm li cas los xij, nws yog cov khoom tseem ceeb siv rau kev tsim khoom xaum ua ntej lub sijhawm ntawd.Lead tau lees paub tias yog cov tshuaj lom neeg heev rau tib neeg.Yog li ntawd, tib neeg tau tshawb nrhiav cov khoom siv los hloov cov hlau lead nrog lwm yam los tsim cov xaum.

Qhov txawv ntawm Graphite thiab Lead yog dab tsi?

Graphite thiab txhuas yog cov tshuaj tseem ceeb vim lawv cov khoom muaj txiaj ntsig thiab kev siv.Qhov sib txawv tseem ceeb ntawm graphite thiab txhuas yog tias graphite yog nontoxic thiab ruaj khov heev, whereas lead yog lom thiab tsis ruaj khov.

Lead yog ib qho uas tsis tshua muaj tshwm sim tom qab hloov pauv hlau.Peb tuaj yeem piav qhia qhov tsis muaj zog hlau ua cim ntawm cov hlau lead siv nws qhov amphoteric xwm.Piv txwv li, txhuas thiab txhuas oxides teb nrog cov kua qaub thiab cov hauv paus thiab zoo li tsim covalent bonds.Cov hmoov txhuas feem ntau muaj +2 oxidation lub xeev ntawm cov hlau lead ntau dua li +4 oxidation xeev (+4 yog qhov feem ntau oxidation rau pawg 14 tshuaj lom neeg).