Nws yog xim hlau daim ntawv cog lus: tsim mechanism. Hlau Tshuaj Kev sib txuas lus:

Tag nrho cov tam sim no lub npe hu tshuaj ntsiab nyob rau hauv lub periodic rooj yog muab faib arbitrarily rau hauv ob pawg: hlau thiab uas tsis yog-hlau. Nyob rau hauv thiaj li yuav ua tsis tau tsuas yog hais thiab cov tebchaw, tshuaj yuav hnov mob nrog txhua lwm yam, lawv yuav tsum muaj nyob rau hauv daim ntawv ntawm tej yam yooj yim thiab complex tebchaw.

Qhov no yog vim li cas ib co electrons tseem tabtom txais yuav, thiab lwm yam - muab. Replenishing txhua lwm yam thiaj li mus ua ntau yam ntsiab thiab tshuaj molecules. Tab sis dab tsi pub rau lawv yuav tsum tau nyob ua ke? Yog vim li cas yog muaj xws li ib tug teeb meem ntawm lub dag lub zog, ua kom puas uas tseem ceeb tshaj qhov txawm lub feem ntau loj heev seev? Thiab lwm leej lwm tus, conversely, yog muab los ntawm lub slightest kev cuam tshuam. Tag nrho cov no yog vim tus tsim ntawm ntau hom ntawm tshuaj bonds ntawm atoms nyob rau hauv molecules txoj kev kev siv lead ua ntxaij ntoo qauv.

Hom tshuaj bonds nyob rau hauv lub tebchaw

Tag nrho cov muaj peev xwm paub qhov txawv plaub hom tshuaj bonds.

1. Covalent nonpolar. Tsim ntawm ob tug zoo tib nonmetals vim sib koom ntawm electrons, txoj kev ua ib qho electron officers. Nyob rau hauv kev kawm ntawv, nws yog kawm unpaired valence hais. Piv txwv: halogens, oxygen, hydrogen, nitrogen, sulfur, phosphorus.
2. Ncov qaumteb qabteb covalent. Tsim ntawm ob tug sib txawv uas tsis yog-hlau los yog ntawm muaj zog heev rau lub zog ntawm cov hlau thiab nonmetal tsis muaj zog nyob rau hauv electronegativity. Lwm thiab kev electron officers thiab rub lawv mus rau nws lub atom, uas nws electron affinity saum toj no. Piv txwv: NH _{3, sic,} P ₂ O ₅ thiab lwm yam.
3. Hydrogen daim ntawv cog lus. Qhov tseem tsis ruaj tsis khov thiab tsis muaj zog, yog tsim ntawm lub mas electronegative atom ntawm ib tug qauv thiab lwm yam zoo. Qhov no tshwm sim feem ntau thaum yaj tshuaj nyob rau hauv dej (cawv, ammonia thiab thiaj li nyob). Tshuav rau xws li ib tug kev twb kev txuas yuav muaj nyob macromolecule cov nqaijrog, nucleic acids, complex carbohydrates, thiab li ntawd.
4. Ionic daim ntawv cog lus. Tsim vim electrostatic txaus nyiam rog raznozaryazhennyh hlau ions thiab uas tsis yog-hlau. Qhov ntau dua qhov txawv nyob rau hauv no Performance index, qhov ntau pronounced yog lub ionic xwm ntawm tus sis. Piv txwv ntawm lub tebchaw: binary ntsev, complex compound - alkali.
5. Nws yog xim hlau daim ntawv cog lus, uas tus mechanism ntawm tsim thiab cov khoom uas yuav tau los sib tham ntxiv. Tsim nyob rau hauv cov hlau, lawv alloys ntawm ntau hom.

Muaj xws li ib tug tshaj plaws raws li txoj kev sib sau ntawm cov tshuaj daim ntawv cog lus. Nws cia li hais tias nws yog tsis yooj yim sua xav txog txhua daim ntawv cog lus benchmark. Lawv yog cov tag nrho xwb lub tsev cim. Tom qab tag nrho, lub hauv paus ntawm tag nrho cov kev sib tshuam yog ib tug hluas hauv paus ntsiab lus - elektronnostaticheskoe sis raug zoo. Yog li ntawd, ionic, nws yog xim hlau, covalent tsevneeg thiab hydrogen muaj ib zaug xwb tshuaj xwm thiab tsuas yog borderline mob mus rau txhua lwm yam.

Co thiab cov lawv lub zog

Co muaj nyob rau hauv feem coob ntawm cov tag nrho cov tshuaj hais. Qhov no yog vim lawv khoom tshwj xeeb. Ib tug tseem ceeb ib feem ntawm uas yog tau ua los ntawm ib tug neeg los ntawm nuclear tshua nyob rau hauv lub laboratory, lawv yog tej nrog luv luv ib nrab-lub neej.

Txawm li cas los, feem ntau - yog tej yam ntuj tso ntsiab uas tsim tag nrho cov pob zeb thiab ores, yog ib feem ntawm lub tseem ceeb tshaj plaws tebchaw. Nws yog vim hais tias ntawm cov neeg no tau kawm rau cam khwb cia alloys thiab tsim ib tug ntau ntawm zoo heev thiab tseem ceeb cov khoom. Qhov no yog xws li tooj liab, hlau, txhuas, nyiaj, kub, chrome, manganese, npib tsib xee, zinc, coj thiab lwm tus neeg.

Rau tag nrho co yeej paub ntau lub zog uas piav txog daim duab nws yog xim hlau daim ntawv cog lus tsim. Yuav ua li cas yog cov yam ntxwv?

1. Malleability thiab ductility. Nws yog lub npe hu hais tias muaj ntau co muaj peev xwm yuav dov cia txawm mus rau lub point ntawm ntawv ci (kub, txhuas). Ntawm lwm yam tau txais ib tug hlau, hlau saj zawg zog los xij, cov khoom muaj peev xwm deformed ntawm lub cev feem, tab sis, ces rov qab los ntawm nws cov kev txiav. Cov no yog cov qualities ntawm co thiab yog hu ua malleability thiab ductility. Yog vim li cas rau qhov no feature - ib tug hlau txuas yam. Lub ions thiab electrons nyob rau hauv lub siv lead ua swb txheeb ze rau txhua tus lwm yam tsis txhaum, uas tso cai rau kom tau khaws cia lub sam xeeb ntawm tag nrho cov qauv.
2. Nws yog xim hlau ci. Qhov no kuj piav txog cov nws yog xim hlau daim ntawv cog lus, tus tsim mechanism ntawm nws tus yam ntxwv thiab nta. Yog li, tsis yog txhua txhua hais yog tau nqus los yog muaj kev cuam tshuam lub teeb tsis muaj sib npaug zos ntev. Atoms feem ntau hlau thiab muaj kev cuam tshuam luv luv-yoj sab ua tshuam uniform silvery xim, dawb, daj xiavlus Hawj txawm. Tsuav txhob yog cov tooj liab thiab kub, lawv yog xim liab-daj thiab liab, ntsig txog. Lawv yog cov tau muaj kev cuam tshuam ntev-wavelength tawg.
3. Thermal thiab hluav taws xob conductivity. Cov zog kuj piav tus siv lead ua ntxaij ntoo qauv thiab nyob rau hauv uas nws tsim yog pom tau hais nws yog xim hlau hom bonds. Vim rau qhov "electron roj" tsiv nyob rau hauv lub siv lead ua, hluav taws xob tam sim no thiab thaum tshav kub kub sai sai thiab evenly faib rau tag nrho cov atoms thiab ions thiab ua los ntawm cov hlau.
4. Cov khoom sau ua ib pawg xeev nyob rau hauv ib txwm tej yam kev mob. Ntawm no, tsuas kos yog mercury. Tag nrho lwm cov co - yog tas muaj zog, khoom sib txuas, raws li zoo raws li lawv alloys. Nws tseem yog lub txiaj ntsim ntawm lub fact tias nyob rau hauv lub xub ntiag ntawm hlau hlau daim ntawv cog lus. Lub mechanism ntawm tsim ntawm no hom ntawm particle losis tswvyim dabtsi zog kiag li paub tseeb hais tias.

Qhov no yooj yim lub cev yam ntxwv rau co, uas piav txog thiab txiav txim raws nraim daim duab nws yog xim hlau daim ntawv cog lus tsim. Cov tebchaw xws txoj kev yog mus hlau atoms ntawm hais, lawv alloys. Qhov ntawd yog rau lawv ib tug khoom thiab ib tug kua hauv lub xeev.

Nws yog xim hlau hom tshuaj daim ntawv cog lus

Yuav ua li cas yog nws feature? Qhov no yog hais tias xws li ib tug kev sib raug zoo yog tsim tsis los ntawm raznozaryazhennyh ions thiab electrostatic attraction thiab tsis vim qhov txawv nyob rau hauv electronegativity thiab cov nyob rau ntawm free electron officers. Xws li ionic, nws yog xim hlau, covalent daim ntawv cog lus muaj ob peb cov xwm sib txawv thiab yus nta ntawm lawv txuas hais.

Tag nrho co yog xam qhovkev yam ntxwv xws li:

• ib tug me me npaum li cas ntawm electrons nyob rau hauv tus txheej zog (tshwj tsis yog rau ib co kev zam, rau cov uas tej zaum yuav muaj 6.7 thiab 8);
• loj atomic voos kheej-kheej;
• tsawg ionization zog.

Tag nrho cov no muaj txhawb rau ib qho yooj yim sib cais ntawm unpaired electrons rau sab tub ntxhais. Nyob rau hauv cov ntaub ntawv no, cov dawb orbitals ntawm lub atom tseem heev npaum li cas. Scheme ntawm lub nws yog xim hlau tsevneeg cia li yuav qhia ntau yam overlapping hlwb sib txawv ntawm cov orbital atoms ntawm lawv tus kheej, uas ua nyob rau hauv lub intracrystalline thiab tsim ib qho chaw. Nws ua hauj lwm pab electrons los ntawm txhua atom uas pib dawb do laij rau ntau qhov chaw ntawm lub ntxaij ntoo. Tej lub sij hawm, txhua tus uas yog txuas mus rau ib tug ion nyob rau hauv lub siv lead ua tsev thiab converts nws mus rau ib tug atom, ces tu dua, txoj kev ua ion.

Yog li, lub nws yog xim hlau daim ntawv cog lus - yog daim ntawv cog lus ntawm atoms, ions thiab dawb electrons nyob rau hauv tag nrho cov hlau lead. Lub electron huab, txav mus dawb do hauv cov qauv, xa mus rau raws li "electron roj". Nws tau piav rau lawv, feem ntau ntawm lub cev muaj zog ntawm hlau thiab lawv cov alloys.

Yuav ua li cas hais siv ib tug nws yog xim hlau tshuaj daim ntawv cog lus? Piv txwv yog sib txawv. Cia peb xav txog ib daim ntawm lithium. Txawm hais tias koj noj nws lub loj ntawm ib tug taum mog, muaj ntau txhiab tus atoms. Yog li ntawd cia peb xav txog tej yam uas txhua tus ntawm cov txhiab tus atoms muab ib tug valence electron nyob rau hauv ib qho crystalline qhov chaw. Nyob rau tib lub sij hawm, paub cov hluav taws xob qauv ntawm lub caij, koj yuav saib tau lub xov tooj tsis muaj orbitals. Thaum lawv lithium yog 3 (lub thib ob p-orbital zog). Peb txhua atom ntawm kaum tawm txhiab - qhov no yog ib qho chaw nyob rau hauv lub siv lead ua, nyob rau lub "electronic roj" tsiv dawb do.

Substance yeej ib txwm muaj zog nws yog xim hlau daim ntawv cog lus. Tom qab tag nrho, lub electron roj tsis pub tus siv lead ua rau lub caij nplooj zeeg, tiam sis tsuas yog muaj kev txav cov khaubncaws sab nraud povtseg thiab ces zaug. Nws glitters muaj ib yam ceev (feem ntau yog siab), fusibility, malleability thiab ductility.

Qhov twg lwm tus pom tau hais nws yog xim hlau daim ntawv cog lus? Piv txwv ntawm tshuaj:

• co li tej yam yooj yim;
• tag nrho cov hlau alloys nrog txhua lwm yam;
• tag nrho cov co thiab lawv alloys nyob rau hauv cov kua thiab khoom hauv lub xeev.

Cov piv txwv yog tsuas ib qho zoo kawg npaum li cas, vim hais tias cov hlau nyob rau hauv lub periodic rooj, ntau tshaj li 80!

Nws yog xim hlau daim ntawv cog lus: tsim mechanism

Yog hais tias peb xav txog nws nyob rau hauv nqe lus dav dav, lub ntsiab lus tseem ceeb peb tau teev saum toj no. Muaj ntawm atomic orbitals thiab electrons yooj yim tu los ntawm lub nucleus vim hais tias ntawm qhov uas tsis muaj ionization zog - yog cov tseem ceeb tej yam kev mob rau cov tsim ntawm no hom ntawm kev sib txuas lus. Yog li, nws zoo nkaus li uas nws yog DVR ntawm cov hauv qab no hais:

• atoms nyob rau hauv tus siv lead ua ntxaij ntoo;
• free electrons, uas nyob ntawm lub valence ntawm cov hlau;
• ions nyob rau hauv lub siv lead ua ntxaij ntoo.

Cov - ib tug nws yog xim hlau daim ntawv cog lus. Lub mechanism ntawm tsim feem ntau qhia los ntawm cov nram qab no nkag: Kuv ^{0 -} e - ↔ kuv ^{n +.} Los ntawm daim duab evidently, tej hlau hais yog tam sim no nyob rau hauv lub siv lead ua.

Muaju lawv tus kheej yuav muaj ntau daim. Nws nyob rau ntawm cov ntaub ntawv uas nrog uas peb yuav soj ntsuam.

Hom hlau muaju

Qhov no qauv ntawm cov hlau los yog nws alloy muaj ib tug heev ntom packing hais. Nws muab ions nyob rau hauv lub siv lead ua qhov chaw. By lawv tus kheej, lattice yuav ua tau sib txawv ntawm cov geometric duab nyob rau hauv qhov chaw.

1. Obemnotsentricheskaya nyhav lattice - alkali hlau.
2. Hexagonal compact qauv - tag nrho cov alkaline, tsuas yog rau barium.
3. Granetsentricheskaya nyhav - txhuas, tooj liab, zinc, ntau txoj kev hloov co.
4. Rhombohedral qauv - cov mercury.
5. Tetragonal - indium.

Cov co heavy thiab lub qis nws yog nyob rau hauv lub periodic system, qhov nyuaj nws yog ntim thiab spatial koom haum ntawm tus siv lead ua. Thaum zoo li no steel tshuaj daim ntawv cog lus, piv txwv ntawm cov uas yuav txo tau rau txhua tus uas twb muaj lawm hlau yog decisive nyob rau hauv kev tsim kho ntawm tus siv lead ua. Alloys muaj ib tug heev ntau haiv neeg koom haum nyob rau hauv qhov chaw, ib txhia ntawm lawv yog cov tseem tsis tau tag nrho to taub.

Kev sib txuas lus specifications: nondirectionality

Covalent thiab hlau daim ntawv cog lus muaj ib tug heev cov lus hais txawv lwm feature. Tsis zoo li cov thawj, cov nws yog xim hlau daim ntawv cog lus yog tsis qhia. Ua li cas nws txhais li cas? Hais tias yog, tus electron huab hauv tus siv lead ua tsiv heev dawb do tsis pub dhau nws nyob rau hauv txawv kev qhia, txhua txhua tus electron muaj peev xwm mus koom kiag li tej ion nyob rau hauv cov qauv ntawm cov ntshav. Hais tias yog, tus sis yog nqa tawm nyob rau hauv txawv kev qhia. Li no, lawv hais tias lub nws yog xim hlau daim ntawv cog lus - tsis-directional.

Lub mechanism ntawm covalent daim ntawv cog lus yuav tsim ntawm qhia electron officers, piv txwv li huab atoms sib tshooj. Thiab nws tshwm sim nruj me ntsis rau ib tug tej yam kab txuas lawv chaw. Yog li ntawd, sib tham txog cov kev taw qhia ntawm xws li ib tug kev twb kev txuas.

saturability

Qhov no yam ntxwv qhia lub peev xwm ntawm lub atoms rau ib tug tsawg los yog unlimited sis raug zoo nrog lwm leej lwm tus. Piv txwv li, covalent thiab hlau daim ntawv cog lus nyob rau hauv qhov ntsuas no dua yog opposites.

Tus thawj yog tag nrho. Atoms muab kev koom tes nyob rau hauv nws tsim yog ib tug taag naj npawb ntawm cov sab nraud valence electrons ncaj qha kev koom tes nyob rau hauv lub tsim ntawm lub compound. Ntau tshaj noj mov, nws yuav tsis tau lub electrons. Yog li ntawd, tus xov tooj ntawm bonds tsim limited valence. Li no saturation vim. Vim li no cov yam ntxwv ntawm feem ntau ntawm cov tebchaw nws muaj ib tug tsis tu ncua tshuaj nyob tus yeees.

Hlau thiab hydrogen bonds, rau lwm cov tes, uas tsis yog-saturating. Qhov no yog vim muaj ntau free electrons thiab orbitals nyob rau hauv lub siv lead ua. Lub luag hauj lwm ua si los ntawm lub ions nyob rau hauv lub siv lead ua ntxaij ntoo qhov chaw, txhua tus uas yuav ua tau ib tug atom thiab ib tug ion dua lub sij hawm.

Lwm cov yam ntxwv ntawm cov nws yog xim hlau daim ntawv cog lus - delocalization nrog electron huab. Nws yog manifested nyob rau hauv lub peev xwm ntawm ib tug me me npaum li cas ntawm electrons qhia txuas tus plurality ntawm co ntawm atomic nuclei. Uas yog, cov kev ceev ntawm delocalized raws li nws yog faib tusyees ntawm tag nrho cov chav ntawm tus siv lead ua.

Piv txwv ntawm txoj kev ua ib daim ntawv cog lus nyob rau hauv tshooj

Xav txog ib tug ob peb yam embodiments, illustrate uas, raws li ib tug nws yog xim hlau daim ntawv cog lus yog tsim. Piv txwv Cov nram qab no tshuaj:

• zinc;
• txhuas;
• poov tshuaj;
• chrome.

Hlau daim ntawv cog lus tsim ntawm zinc atoms: ZN ^{0 -} 2e - ↔ ZN ^2+. zinc atom muaj plaub zog. Dawb orbitals raws li nyob rau hauv lub tshuab hluav taws xob qauv, nws muaj 15 - 3 p orbitals, 4 d 5 thiab 7 nyob rau 4F. Hauv cov qauv muaj xws li: 1s 2s ^{2 2 2} 2p ⁶ 3s 3p ⁶ 4s ² 3d ¹⁰ 4d 4p ^{0 0 0} 4F, tsuas 30 electrons atom. Hais tias yog, ob free valence tsis zoo hais yuav tau tsiv mus nyob rau hauv lub 15 khab seeb thiab tsis muaj leej twg nyob orbitals. Thiab yog li ntawd txhua atom. Cov - ib tug loj loj zuag qhia tag nrho qhov chaw uas muaj tas orbitals, thiab ib tug me me npaum li cas ntawm electrons txuas tag nrho cov qauv ua ke.

Lub nws yog xim hlau daim ntawv cog lus ntawm txhuas atoms: AL ^{0 -} e - ↔ AL ^3+. Kaum peb electrons txhuas atoms nyob rau ntawm peb lub zog ntau ntau, lawv yog kom meej meej tsis nyob rau hauv abundance. Hauv cov qauv: 1s 2s ^{2 2} 2p ⁶ 3s 3p ^{1 2 0} 3d. Dawb orbitals - 7 daim. Obviously, cov electron huab yuav tau me me piv nrog rau tag nrho cov sab hauv qhov chaw dawb rau hauv lub siv lead ua.

Lub nws yog xim hlau daim ntawv cog lus chromium. Qhov no xyov lub caij uas lawv siv hluav taws xob qauv. Tom qab tag nrho, rau stabilizing lub system tsis ua hauj lwm muaj tshwm sim nrog electron 4s 3D orbital: 1s 2s ² 2p ^{2 6 2} 3s 4s 3p ^{6 1 5} 4p 3d 4d ^{0 0 0} 4F. Tsuas yog 24 electron valence uas yog rau. Lawv mus rau cov hluav taws xob qhov chaw nyob rau hauv lub tsim ntawm ib tug tshuaj daim ntawv cog lus. Dawb orbitals 15, uas yog tseem loj dua uas yuav tsum tau mus sau. Yog li ntawd, chromium - raws li ib tug raug piv txwv ntawm ib tug hlau nrog ib tug coj daim ntawv cog lus nyob rau hauv lub molecule.

Ib qho ntawm feem active co uas hnov mob txawm nrog zoo tib yam dej rau hluav taws, yog poov tshuaj. Yuav ua li cas tso nyiaj rau tej zog? Ib zaug ntxiv, nyob rau hauv ntau lub respects - nws yog xim hlau hom daim ntawv cog lus. Electrons nyob rau hauv lub caij tsuas 19, tab sis lawv muaj nyob rau ntau li ntau raws li 4 zog. Qhov ntawd yog 30 ntau orbitals sublevels. Hauv cov qauv: 1s 2s ² 2p ^{2 6 2} 3s 4s 3p ^{6 1 0} 4p 3d 4d ^{0 0 0} 4F. Tsuas yog ob valence electrons nrog heev tsawg ionization zog. Dawb tuaj tawm thiab mus rau cov hluav taws xob qhov chaw. Orbitals yuav tsiv mus nyob ib atom daim 22, i.e. ib tug heev uas nws kim heev qhov chaw rau lub "electron roj".

Zoo sib xws thiab sib txawv nrog lwm yam bonds

Nyob rau hauv dav dav, lub qhov teeb meem twb tau sib tham saum toj no. Ib tug yuav tsuas generalize thiab kos ib xaus. Lub ntsiab txawv los ntawm tag nrho cov lwm yam kev sib txuas lus nta yog cov hlau muaju yog:

• ob peb hom hais koom nyob rau hauv tus txheej txheem ntawm losis tswvyim dabtsi (atoms, ions los yog atoms, ions, electrons);
• txawv spatial geometric qauv ntawm muaju.

Nrog hydrogen thiab ionic hlau combines satiation thiab undirected. Nrog covalent ncov qaumteb qabteb - muaj zog electrostatic attraction ntawm hais. Nyias, ion - hom hais nyob rau hauv lub crystalline lattice cov ntsiab lus (ions). Nrog covalent nonpolar - atoms nyob rau hauv tus siv lead ua qhov chaw.

Hom bonds nyob rau hauv cov hlau ntawm txawv sau ua ib pawg xeev

Raws li peb tau sau tseg saum toj no, nws yog xim hlau tshuaj daim ntawv cog lus, piv txwv ntawm cov uas yuav muab nyob rau hauv tsab xov xwm, yog tsim nyob rau hauv ob lub xeev ntawm aggregation ntawm hlau thiab lawv cov alloys: khoom thiab kua.

Cov lus nug no: li cas hom ntawm kev twb kev txuas mus rau lub hlau vapor? A: Covalent ncov qaumteb qabteb thiab nonpolar. Raws li nrog rau tag nrho cov tebchaw tam sim no nyob rau hauv ib tug roj. Uas yog tsis ntuag thiab tus siv lead ua qauv yog retained thaum lub sij hawm heev cua sov ntawm cov hlau thiab hloov nws los ntawm khoom ua kua kev sib txuas lus. Txawm li cas los, thaum nws los mus rau cov hloov ua kua rau lub vapor lub xeev, tus siv lead ua puas lawm thiab nws yog xim hlau daim ntawv cog lus yog hloov dua siab tshiab rau covalent.