Raws li koj paub, chemistry kawm txog cov qauv thiab cov khoom ntawm cov khoom, nrog rau lawv cov kev sib hloov pauv. Ib qho chaw tseem ceeb hauv kev ua tus cwj pwm ntawm cov tshuaj sib xyaw ua ke yog nyob ntawm cov lus nug ntawm seb lawv muaj pes tsawg. Nws tuaj yeem yog atom, ions lossis molecules. Nyob rau hauv cov khib nyiab, lawv nkag mus rau hauv cov pob txha ntawm crystal lattices. Cov qauv molecular muaj ib tug me me ntawm cov tebchaw nyob rau hauv cov khoom, kua thiab gaseous xeev.
Nyob rau hauv peb tsab xov xwm, peb yuav muab piv txwv ntawm cov khoom uas yog tus cwj pwm los ntawm molecular siv lead ua lattices, thiab kuj xav txog ob peb hom intermolecular kev sib tshuam yam ntxwv ntawm cov khib nyiab, kua thiab gases.
Vim li cas koj yuav tsum paub cov qauv ntawm cov tshuaj sib xyaws
Nyob rau hauv txhua ceg ntawm tib neeg kev paub, ib qho tuaj yeem tawm ib pab pawg ntawm cov kev cai lij choj uas tsim los ntawm kev tshawb fawb ntxiv. hauv chemistry- Qhov no yog txoj kev xav ntawm M. V. Lomonosov thiab J. D alton, piav qhia txog atomic thiab molecular qauv ntawm cov teeb meem. Raws li cov kws tshawb fawb tau tsim, paub txog cov qauv sab hauv, nws muaj peev xwm kwv yees ob lub cev thiab tshuaj lom neeg ntawm cov khoom sib xyaw. Tag nrho cov nyiaj loj ntawm cov khoom siv dag zog tsim los ntawm tus txiv neej (yas, tshuaj, tshuaj tua kab, thiab lwm yam) tau txiav txim siab cov yam ntxwv thiab cov khoom muaj txiaj ntsig zoo tshaj plaws rau nws txoj kev lag luam thiab tsev neeg.
Kev paub txog cov yam ntxwv ntawm cov qauv thiab cov khoom ntawm cov khoom sib txuas yog qhov xav tau thaum ua cov ntu tswj, kev xeem thiab kev xeem hauv chav kawm ntawm chemistry. Piv txwv li, hauv daim ntawv teev cov tshuaj, nrhiav cov lus teb kom raug: cov tshuaj twg muaj cov qauv molecular?
- Zinc.
- pob zeb diamond.
- Naphthalene.
YMagnesium oxide.
Cov lus teb raug yog: zinc muaj cov qauv molecular, nrog rau naphthalene.
Kev sib cuam tshuam ntawm intermolecular
Nws tau raug sim tsim tias cov qauv molecular yog cov yam ntxwv ntawm cov khoom uas muaj cov ntsiab lus melting tsawg thiab tsawg hardness. Yuav ua li cas ib tug yuav piav qhia txog qhov fragility ntawm cov siv lead ua lattices ntawm cov tebchaw? Raws li nws tau muab tawm, txhua yam nyob ntawm lub zog ntawm kev sib koom ua ke ntawm cov khoom nyob rau hauv lawv cov nodes. Nws muaj qhov hluav taws xob zoo thiab hu ua kev sib cuam tshuam hauv nruab nrab lossis van der Waals rog, uas yog ua raws li kev cuam tshuam ntawm cov khoom siv hluav taws xob sib txawv - dipoles - ntawm ib leeg. Nws muab tawm hais tias muaj ntau yam mechanisms rau lawv tsim,nyob ntawm qhov xwm ntawm nws tus kheej.
Acids as compounds of molecular composition
Txoj kev daws teeb meem ntawm cov kua qaub feem ntau, ob qho tib si organic thiab inorganic, muaj cov ntsiab lus polar uas yog taw qhia txog ib leeg nrog cov ncej sib txawv. Piv txwv li, nyob rau hauv ib qho kev daws ntawm hydrochloric acid HCI muaj dipoles, ntawm qhov kev taw qhia kev sib cuam tshuam tshwm sim. Nrog rau qhov kub thiab txias, molecules ntawm hydrochloric, hydrobromic (HBr) thiab lwm yam halogen-muaj acids muaj ib tug txo nyob rau hauv lub orientation nyhuv, vim hais tias cov thermal zog ntawm cov hais cuam tshuam rau lawv kev sib nrig sib attraction. Ntxiv rau cov khoom siv saum toj no, sucrose, naphthalene, ethanol thiab lwm cov organic tebchaw muaj cov qauv molecular.
How induced charged particles are made
Ua ntej, peb suav hais tias yog ib qho ntawm cov txheej txheem ntawm kev ua ntawm Van der Waals rog, hu ua kev sib cuam tshuam kev taw qhia. Ntxiv nrog rau cov organic tshuaj thiab halogen-muaj cov kua qaub, hydrogen oxide, dej, muaj cov qauv molecular. Hauv cov khoom uas tsis yog-polar, tab sis nquag tsim cov dipoles, molecules, xws li carbon dioxide CO2, ib tus tuaj yeem soj ntsuam cov tsos ntawm induced charged hais - dipoles. Lawv cov cuab yeej tseem ceeb tshaj plaws yog lub peev xwm los sib nyiam vim qhov pom ntawm electrostatic attraction rog.
Molecular qauv ntawm roj
Nyob rau hauv lub subheading dhau los, peb tau hais txog cov pa roj carbon dioxide compound. Txhua ntawm nws cov atoms tsim ib qho hluav taws xob nyob ib ncig ntawm nws tus kheej, uas inducespolarization ib atom ntawm ib tug nyob ze carbon dioxide molecule. Nws hloov mus rau hauv ib lub dipole, uas, nyob rau hauv lem, yuav muaj peev xwm ntawm polarizing lwm CO2 hais. Yog li ntawd, cov molecules yog attracted rau ib leeg. Kev sib cuam tshuam inductive kuj tuaj yeem pom nyob rau hauv cov khoom uas muaj cov polar particles, txawm li cas los xij, qhov no nws tsis muaj zog dua li cov kev taw qhia van der Waals rog.
Kev sib cais sib cais
Ob lub atoms lawv tus kheej thiab cov khoom uas ua rau lawv (nucleus, electrons) muaj peev xwm ntawm kev sib hloov mus tas li thiab oscillatory. Nws ua rau cov tsos ntawm dipoles. Raws li kev tshawb fawb ntawm quantum mechanics, qhov tshwm sim ntawm instantaneous doubly charged hais tshwm sim ob qho tib si nyob rau hauv cov khib nyiab thiab nyob rau hauv cov kua synchronously, thiaj li hais tias qhov kawg ntawm cov molecules nyob ze tig tawm mus rau opposite ncej. Qhov no ua rau lawv cov electrostatic attraction, hu ua kev sib cuam tshuam dispersion. Nws yog tus yam ntxwv ntawm tag nrho cov khoom, tshwj tsis yog cov uas nyob rau hauv ib tug gaseous xeev, thiab nws cov molecules yog monatomic. Txawm li cas los xij, van der Waals rog tuaj yeem tshwm sim, piv txwv li, thaum lub sijhawm hloov pauv ntawm inert gases (helium, neon) mus rau hauv cov kua theem ntawm qhov kub thiab txias. Yog li, cov qauv molecular ntawm lub cev lossis cov kua dej txiav txim siab lawv lub peev xwm los tsim ntau hom kev sib cuam tshuam ntawm kev sib cuam tshuam: kev taw qhia, induced lossis dispersion.
Dab tsi yog sublimation
Molecular qauv ntawm cov khoom, xws li iodine crystals,ua rau muaj qhov tshwm sim ntawm lub cev zoo li sublimation - volatilization ntawm I 2molecules nyob rau hauv daim ntawv ntawm violet vapors. Nws tshwm sim los ntawm qhov chaw ntawm cov khoom nyob rau hauv cov khoom theem, bypassing lub xeev cov kua.
Qhov kev sim pom qhov pom tau zoo no feem ntau ua tiav hauv cov chav kawm chemistry hauv tsev kawm los qhia txog cov yam ntxwv ntawm cov khoom siv lead ua molecular thiab cov khoom sib txuas ntawm cov khoom sib txuas. Feem ntau cov no yog cov hardness tsawg, tsawg melting thiab boiling point, tsis zoo thermal thiab hluav taws xob conductivity, thiab volatility.
siv tswv yim paub txog cov qauv ntawm cov khoom
Raws li peb tau pom, qee qhov kev sib raug zoo tuaj yeem tsim los ntawm hom siv lead ua lattice, qauv thiab cov khoom ntawm cov khoom sib xyaw. Yog li ntawd, yog hais tias tus yam ntxwv ntawm ib yam khoom yog paub, ces nws yog heev yooj yim mus twv seb cov yam ntxwv ntawm nws cov qauv thiab muaj pes tsawg leeg ntawm hais: atoms, molecules los yog ions. Cov ntaub ntawv tau txais kuj tseem yuav pab tau yog tias ua haujlwm hauv chemistry nws yog ib qho tsim nyog los xaiv cov khoom uas muaj cov qauv molecular los ntawm ib pawg ntawm cov tebchaw, tsis suav nrog cov uas muaj atomic lossis ionic hom lattices.
Summing li, peb tuaj yeem xaus cov hauv qab no: cov qauv molecular ntawm lub cev muaj zog, thiab nws cov qauv spatial ntawm crystal lattices, thiab kev npaj ntawm polarized hais nyob rau hauv cov kua thiab gases yog tag nrho lub luag hauj lwm rau nws lub cev thiab tshuaj. Hauv cov ntsiab lus theoretical, cov khoom ntawm cov tebchaw,muaj cov dipoles nyob ntawm seb qhov loj ntawm lub zog ntawm kev sib cuam tshuam ntawm intermolecular. Qhov siab dua qhov polarity ntawm cov molecules thiab qhov me me ntawm lub vojvoog ntawm cov atoms uas ua rau lawv, qhov muaj zog ntawm kev taw qhia lub zog uas tshwm sim ntawm lawv. Ntawm qhov tsis sib xws, qhov loj dua cov atoms uas tsim cov molecule, qhov siab dua nws lub sij hawm dipole, thiab, yog li ntawd, qhov tseem ceeb ntawm lub zog dispersion. Yog li, cov qauv molecular ntawm cov khoom tseem cuam tshuam rau kev sib cuam tshuam ntawm nws cov khoom - dipoles.
