Ib qho ntawm cov khoom siv tshaj plaws uas tib neeg ib txwm nyiam ua haujlwm nrog yog hlau. Hauv txhua lub sijhawm, qhov kev nyiam tau muab rau ntau hom ntawm cov khoom zoo kawg no. Yog li, IV-III millennia BC raug suav hais tias yog hnub nyoog ntawm Chalcolith, lossis tooj liab. Tom qab ntawd nws tau hloov los ntawm tooj liab, thiab tom qab ntawd qhov tseem ceeb niaj hnub no - hlau los rau hauv quab yuam.
Hnub no feem ntau nyuaj rau xav txog tias nws yog ib zaug ua tau yam tsis muaj cov khoom siv hlau, vim tias yuav luag txhua yam, los ntawm cov khoom siv hauv tsev, cov cuab yeej kho mob thiab xaus nrog cov khoom hnyav thiab lub teeb, muaj cov khoom siv no lossis suav nrog cov khoom sib cais. ntawm nws. Vim li cas hlau thiaj tswj tau qhov muaj koob meej? Dab tsi yog cov yam ntxwv thiab qhov nws muaj nyob hauv lawv cov qauv, cia peb sim ua kom paub ntxiv.
tswvyim dav dav ntawm cov hlau
"Chemistry. Qib 9" yog phau ntawv uascov me nyuam kawm ntawv. Nws yog nyob rau hauv nws cov hlau yog kawm nyob rau hauv kom meej. Kev txiav txim siab ntawm lawv lub cev thiab tshuaj lom neeg yog mob siab rau rau tshooj loj, vim tias lawv qhov sib txawv yog qhov loj heev.
Nws yog los ntawm lub hnub nyoog no uas tau pom zoo kom muab cov me nyuam lub tswv yim txog cov atoms thiab lawv cov khoom, vim tias cov tub ntxhais hluas muaj peev xwm txaus siab rau qhov kev paub zoo li no. Lawv pom zoo tias ntau yam ntawm cov khoom, tshuab thiab lwm yam nyob ib puag ncig lawv yog raws li cov khoom siv hlau.
Dab tsi yog hlau? Los ntawm qhov pom ntawm chemistry, nws yog kev cai xa mus rau cov atoms li cov uas muaj:
- ib tug me me ntawm cov electrons nyob rau sab nrauv;
- show muaj zog kho cov khoom;
- muaj lub vojvoog loj atomic;
- Yuav ua li cas cov tshuaj yooj yim muaj ntau lub cev tshwj xeeb.
Lub hauv paus ntawm kev paub txog cov tshuaj no tuaj yeem tau los ntawm kev xav txog cov qauv atomic-crystal ntawm cov hlau. Nws piav qhia tag nrho cov yam ntxwv thiab cov khoom ntawm cov tshuaj no.
Nyob rau hauv lub caij nyoog rau cov hlau, feem ntau ntawm tag nrho cov lus tau faib, vim lawv tsim tag nrho cov pab pawg thib ob thiab cov tseem ceeb ntawm thawj mus rau pawg thib peb. Yog li ntawd, lawv cov lej superiority yog pom tseeb. Feem ntau yog:
- calcium;
- sodium;
- titanium;
- iron;
- magnesium;
- aluminium;
- poov tshuaj.
Txhua cov hlau muaj ntau yam khoom uas tso cai rau lawv los ua ke rau hauv ib pawg loj ntawm cov khoom. Nyob rau hauv lem, nws yog cov qauv siv lead ua ntawm cov hlau uas piav txog cov khoom no.
Khoom ntawm cov hlau
Cov khoom tshwj xeeb ntawm cov tshuaj hauv qab no suav nrog cov hauv qab no.
- Hlau ci. Txhua tus neeg sawv cev ntawm cov khoom yooj yim muaj nws, thiab feem ntau ntawm lawv muaj tib xim nyiaj-dawb. Tsuas yog ob peb (kub, tooj, alloys) txawv.
- Malleability thiab plasticity - lub peev xwm deform thiab rov qab tau yooj yim txaus. Rau cov neeg sawv cev sib txawv nws tau nthuav tawm rau qhov sib txawv.
- Hluav taws xob thiab thermal conductivity yog ib qho ntawm cov khoom tseem ceeb uas txiav txim siab txog cov hlau thiab nws cov alloys.
Cov qauv siv lead ua ntawm cov hlau thiab alloys piav qhia vim li cas rau txhua yam ntawm cov khoom qhia thiab hais txog lawv qhov hnyav hauv txhua tus neeg sawv cev. Yog tias koj paub cov yam ntxwv ntawm cov qauv zoo li no, koj tuaj yeem cuam tshuam cov khoom ntawm cov qauv thiab kho nws mus rau qhov kev xav tau, uas tib neeg tau ua rau ntau xyoo lawm.
Atomic crystal qauv ntawm cov hlau
Tus qauv zoo li cas, nws yog dab tsi? Lub npe nws tus kheej qhia tias tag nrho cov hlau yog crystals nyob rau hauv cov khoom, uas yog, nyob rau hauv ib txwm tej yam kev mob (tshwj tsis yog rau mercury, uas yog ib tug kua). Crystal yog dab tsi?
Nov yog cov duab kos duab tsim los ntawm kev hla cov kab kev xav los ntawm cov atoms uas kab hauv lub cev. Hauv lwm lo lus, txhua lub hlau yog tsim los ntawm atoms. Lawv nyob hauv nws tsis yog randomly, tab sis tsis tu ncua thiab tsis tu ncua. Yog li ntawd, yog hais tias lub hlwbmuab tag nrho cov khoom no rau hauv ib lub qauv, koj tau txais cov duab zoo nkauj nyob rau hauv daim ntawv ntawm lub cev geometric li niaj zaus ntawm txhua yam duab.
Qhov no yog qhov hu ua Crystal lattice ntawm cov hlau. Nws yog heev complex thiab spatial voluminous, yog li ntawd, rau simplicity, tsis yog tag nrho cov ntawm nws yog qhia, tab sis tsuas yog ib feem, ib tug elementary cell. Cov txheej txheem ntawm cov hlwb no, coj los ua ke thiab xav txog hauv qhov chaw peb sab, tsim cov lattices siv lead ua. Chemistry, physics thiab hlau science yog kev tshawb fawb uas kawm txog cov qauv ntawm cov qauv no.
Lub hauv paus ntawm tes nws tus kheej yog ib pawg ntawm cov atoms uas nyob ntawm qhov deb ntawm ib leeg thiab koom tes nruj nruj ntawm lwm cov khoom nyob ib puag ncig lawv. Nws yog tus cwj pwm los ntawm cov ntim ntom ntom ntom, qhov kev ncua deb ntawm cov txheej txheem ua ntu zus, thiab tus lej sibntsuam. Feem ntau, tag nrho cov kev ntsuas no yog cov yam ntxwv ntawm tag nrho cov siv lead ua, thiab yog li ntawd muaj kev cuam tshuam cov khoom uas pom los ntawm cov hlau.
Muaj ntau ntau yam ntawm cov iav siv lead ua. Tag nrho cov ntawm lawv yog sib sau ua ke los ntawm ib tug feature - muaj atoms nyob rau hauv cov nodes, thiab nyob rau hauv muaj ib tug huab ntawm electron gas, uas yog tsim los ntawm lub dawb txav ntawm electrons nyob rau hauv lub crystal.
Nyob ntawm siv lead ua lattices
Kaum plaub txoj kev xaiv rau cov qauv ntawm lub lattice feem ntau ua ke ua peb hom tseem ceeb. Lawv yog cov hauv qab no:
- Centered Cubic.
- Hexagonal kaw-packed.
- Face-centered cubic.
Cov qauv siv lead ua ntawm cov hlau tsuas yog kawm los ntawm electron microscopy, thaum nws tuaj yeem tau txais cov duab loj loj. Thiab kev faib tawm ntawm cov lattices yog thawj zaug qhia los ntawm Fab Kis tus kws tshawb fawb Bravais, los ntawm lawv lub npe qee zaum hu ua.
Lub cev-Centered Lattice
Cov qauv ntawm cov siv lead ua lattice ntawm cov hlau ntawm hom no yog cov qauv hauv qab no. Qhov no yog ib lub voos xwmfab, ntawm cov nodes uas muaj yim atoms. Lwm qhov yog nyob rau hauv nruab nrab ntawm qhov chaw dawb sab hauv ntawm tes, uas piav qhia lub npe "lub cev-centered".
Qhov no yog ib qho ntawm cov kev hloov pauv ntawm cov qauv yooj yim tshaj plaws ntawm lub hauv paus ntawm tes, thiab yog li tag nrho cov lattice tag nrho. Cov hlau hauv qab no muaj hom no:
- molybdenum;
- vanadium;
- chrome;
- manganese;
- alpha hlau;
- betta-hlau thiab lwm yam.
Cov khoom tseem ceeb ntawm cov neeg sawv cev zoo li no yog qib siab ntawm malleability thiab ductility, hardness thiab lub zog.
ntsej muag-centered lattice
Cov qauv siv lead ua ntawm cov hlau uas muaj lub ntsej muag-centered cubic lattice yog cov qauv hauv qab no. Qhov no yog lub voos xwmfab, uas suav nrog kaum plaub atoms. Yim ntawm lawv tsim cov lattice nodes, thiab rau qhov ntxiv nyob rau ntawm ib lub ntsej muag.
Lawv muaj cov qauv zoo sib xws:
- aluminium;
- nickel;
- lead;
- gamma hlau;
- copper.
Qhov txawv qhov tseem ceeb - ciCov xim sib txawv, lub teeb, lub zog, malleability, muaj zog tiv thaiv corrosion.
Hexagonal lattice
Cov qauv siv lead ua ntawm cov hlau nrog hom lattice no yog raws li hauv qab no. Lub hauv paus ntawm tes yog ua los ntawm hexagonal prism. Muaj 12 atoms nyob rau hauv nws cov nodes, ob tug ntxiv ntawm lub hauv paus thiab peb atoms dawb do nyob rau hauv qhov chaw nyob rau hauv qhov chaw ntawm lub qauv. Kaum xya atoms tag nrho.
Metals xws li:
muaj qhov zoo sib xws
- alpha titan;
- magnesium;
- alpha cob alt;
- zinc.
Main properties - siab zog, muaj zog nyiaj luster.
Tsis zoo hauv cov qauv siv lead ua ntawm cov hlau
Txawm li cas los xij, txhua yam kev xav ntawm cov hlwb yuav muaj qhov tsis zoo, lossis hu ua qhov tsis xws luag. Qhov no tej zaum yuav yog vim muaj ntau yam: txawv teb chaws atoms thiab impurities nyob rau hauv hlau, sab nraud influences, thiab lwm yam.
Yog li ntawd, muaj kev faib tawm uas qhia txog qhov tsis xws luag uas siv lead ua lattices tuaj yeem muaj. Chemistry raws li kev tshawb fawb txog lawv txhua tus txhawm rau txheeb xyuas qhov ua rau thiab kho kom cov khoom ntawm cov khoom tsis hloov pauv. Yog li qhov tsis xws luag yog raws li hauv qab no.
- Point. Lawv tuaj nyob rau hauv peb hom: vacancy, impurities, los yog dislocated atoms. Lawv ua rau muaj qhov tsis zoo ntawm cov khoom sib nqus ntawm cov hlau, nws cov hluav taws xob thiab thermal conductivity.
- Linear, lossis dislocation. Muab cov marginal thiab ntsia hlau. Degrade lub zog thiab zoo ntawm cov khoom.
- Ntogqhov tsis xws luag. Ua rau cov tsos thiab cov qauv ntawm cov hlau.
Tam sim no, txoj hauv kev tau tsim los tshem tawm qhov tsis xws luag thiab tau txais cov pob zeb ntshiab. Txawm li cas los xij, lawv tsis tuaj yeem raug tshem tawm tag nrho, qhov zoo tshaj plaws siv lead ua lattice tsis muaj.
Tus nqi ntawm kev paub txog cov qauv siv lead ua ntawm cov hlau
Los ntawm cov khoom siv saum toj no, nws pom tseeb tias kev paub txog cov qauv zoo thiab cov qauv ua rau nws muaj peev xwm kwv yees cov khoom ntawm cov khoom thiab cuam tshuam rau lawv. Thiab qhov no tso cai rau koj los ua kev tshawb fawb ntawm chemistry. Qib 9 ntawm lub tsev kawm ntawv kev kawm dav dav tsom rau kev qhia cov tub ntxhais kawm kom nkag siab meej txog qhov tseem ceeb ntawm cov laj thawj tseem ceeb: kev sib xyaw - qauv - khoom - daim ntawv thov.
Cov ntaub ntawv hais txog cov qauv siv lead ua ntawm cov hlau qhia qhov kev sib raug zoo no kom meej meej thiab tso cai rau tus kws qhia kom meej meej thiab qhia cov menyuam yaus tias nws tseem ceeb npaum li cas kom paub cov qauv zoo kom raug thiab siv tau txhua yam khoom.
