Txhua yam ntawm cov tshuaj muaj nyob rau hauv lub plhaub ntawm lub ntiaj teb: huab cua, lithosphere thiab hydrosphere - tuaj yeem ua tus piv txwv zoo, lees paub qhov tseem ceeb ntawm txoj kev xav ntawm atomic thiab molecular thiab txoj cai raws sij hawm. Lawv tau tsim los ntawm luminaries ntawm natural science - Lavxias teb sab kws tshawb fawb M. V. Lomonosov thiab D. I. Mendeleev. Lanthanides thiab actinides yog ob tsev neeg uas muaj 14 tshuaj lom neeg txhua tus, nrog rau cov hlau lawv tus kheej - lanthanum thiab actinium. Lawv cov khoom - ob lub cev thiab tshuaj - yuav raug txiav txim siab los ntawm peb hauv daim ntawv no. Tsis tas li ntawd, peb yuav tsim kom muaj txoj haujlwm nyob rau hauv lub sij hawm ntawm hydrogen, lanthanides, actinides nyob ntawm seb cov qauv ntawm cov hluav taws xob orbitals ntawm lawv cov atoms.
Discovery keeb kwm
Thaum kawg ntawm lub xyoo pua 18th, Y. Gadolin tau txais thawj qhov sib xyaw los ntawm cov pab pawg ntawm cov hlau tsis tshua muaj ntiaj teb - yttrium oxide. Txog thaum pib ntawm lub xyoo pua 20th, ua tsaug rau kev tshawb fawb ntawm G. Moseley hauv chemistry, nws tau paub txog qhov muaj nyob ntawm ib pawg hlau. Lawv tau nyob hauv lub caij nyoog nruab nrab ntawm lanthanum thiab hafnium. Lwm yam tshuaj lom neeg - actinium, zoo li lanthanum, tsim ib tsev neeg ntawm 14 xov tooj cuaCov tshuaj hu ua actinides. Lawv qhov kev tshawb pom hauv science tau tshwm sim los ntawm 1879 mus rau nruab nrab ntawm lub xyoo pua 20th. Lanthanides thiab actinides muaj ntau qhov sib xws hauv ob qho tib si lub cev thiab tshuaj lom neeg. Qhov no tuaj yeem piav qhia los ntawm kev teeb tsa ntawm cov khoom siv hluav taws xob hauv cov atoms ntawm cov hlau, uas yog nyob rau theem ntawm lub zog, piv txwv li, rau lanthanides qhov no yog qib plaub f-sublevel, thiab rau actinides - qib tsib f-sublevel. Tom ntej no, peb yuav xav txog lub plhaub hluav taws xob ntawm cov atoms ntawm cov hlau saum toj no kom ntxaws ntxiv.
Tus qauv ntawm cov kev hloov pauv sab hauv hauv lub teeb ntawm atomic thiab molecular qhia
Qhov kev tshawb pom zoo ntawm cov qauv ntawm cov tshuaj los ntawm MV Lomonosov yog lub hauv paus rau kev kawm ntxiv txog cov hluav taws xob ntawm cov atoms. Tus qauv Rutherford ntawm cov qauv ntawm cov qauv ntawm cov ntsiab lus ntawm cov khoom siv tshuaj, cov kev tshawb fawb ntawm M. Planck, F. Gund tau tso cai rau cov kws kho mob kom pom cov lus piav qhia tseeb rau cov qauv uas twb muaj lawm ntawm kev hloov pauv hauv lub cev thiab tshuaj lom neeg uas ua rau lanthanides thiab actinides. Nws yog tsis yooj yim sua kom tsis quav ntsej lub luag hauj lwm tseem ceeb ntawm lub sij hawm txoj cai ntawm D. I. Mendeleev nyob rau hauv txoj kev tshawb no ntawm cov qauv ntawm atoms ntawm kev hloov cov ntsiab lus. Cia peb nyob ntawm qhov teeb meem no kom ntxaws ntxiv.
Qhov chaw ntawm kev hloov pauv sab hauv hauv D. I. Mendeleev's Periodic Table
Nyob rau hauv pab pawg thib peb ntawm thib rau - lub sijhawm loj - qab lanthanum yog ib tsev neeg ntawm cov hlau xws li cerium mus rau lutetium suav nrog. Lub 4f sublevel ntawm lub lanthanum atom yog khoob, thaum lub lutetium atom yog tag nrho cov 14th.electrons. Cov ntsiab lus nyob nruab nrab ntawm lawv yog maj mam sau f-orbitals. Hauv tsev neeg ntawm actinides - los ntawm thorium mus rau lawrencium - tib lub hauv paus ntsiab lus ntawm tsub zuj zuj ntawm cov khoom tsis zoo yog pom nrog qhov sib txawv xwb: sau nrog electrons tshwm sim ntawm 5f sublevel. Cov qauv ntawm lub zog sab nraud thiab tus naj npawb ntawm qhov tsis zoo ntawm nws (sib npaug rau ob) yog tib yam rau tag nrho cov hlau saum toj no. Qhov tseeb no teb cov lus nug ntawm yog vim li cas cov lanthanides thiab actinides, hu ua kev hloov pauv sab hauv, muaj ntau yam zoo sib xws.
Hauv qee qhov chaw ntawm cov ntaub ntawv tshuaj, cov neeg sawv cev ntawm ob tsev neeg tau muab tso ua ke rau hauv pab pawg thib ob. Lawv muaj ob lub hlau los ntawm txhua tsev neeg. Nyob rau hauv daim ntawv luv luv ntawm cov txheej txheem ntawm cov tshuaj lom neeg ntawm DI Mendeleev, cov neeg sawv cev ntawm cov tsev neeg no tau sib cais los ntawm lub rooj nws tus kheej thiab muab tso rau hauv cov kab sib cais. Yog li ntawd, txoj hauj lwm ntawm lanthanides thiab actinides nyob rau hauv lub periodic system sib haum mus rau lub dav dav txoj kev npaj ntawm cov qauv ntawm atoms thiab lub sij hawm ntawm kev sau cov theem nrog electrons, thiab lub xub ntiag ntawm tib lub xeev oxidation ua rau lub koom haum ntawm cov kev hloov nyob rau hauv cov hlau nyob rau hauv cov pab pawg neeg.. Hauv lawv, cov khoom siv tshuaj muaj cov yam ntxwv thiab cov khoom sib npaug rau lanthanum lossis actinium. Yog vim li cas cov lanthanides thiab actinides raug tshem tawm ntawm lub rooj ntawm cov tshuaj.
Yuav ua li cas cov hluav taws xob configuration ntawm f-sublevel cuam tshuam cov khoom ntawm hlau
Raws li peb tau hais ua ntej, txoj haujlwm ntawm lanthanides thiab actinides nyob rau lub sijhawmsystem ncaj qha txiav txim lawv lub cev thiab tshuaj yam ntxwv. Yog li, ions ntawm cerium, gadolinium, thiab lwm yam khoom ntawm tsev neeg lanthanide muaj lub sijhawm sib nqus siab, uas cuam tshuam nrog cov qauv ntawm f-sublevel. Qhov no ua rau nws tuaj yeem siv hlau ua dopants kom tau txais cov khoom siv hluav taws xob nrog cov khoom sib nqus. Sulfides ntawm cov ntsiab lus ntawm tsev neeg actinium (piv txwv li, sulfide ntawm protactinium, thorium) nyob rau hauv muaj pes tsawg leeg ntawm lawv cov molecules muaj ib tug sib tov ntawm tshuaj daim ntawv cog lus: ionic-covalent los yog covalent-hlau. Qhov no feature ntawm cov qauv coj mus rau qhov tshwm sim ntawm ib tug tshiab physicochemical khoom thiab ua hauj lwm raws li ib tug teb rau lo lus nug ntawm yog vim li cas lanthanides thiab actinides muaj luminescent zog. Piv txwv li, ib qho piv txwv ntawm anemone uas yog silvery nyob rau hauv qhov tsaus ntuj glows nrog ib tug bluish glow. Qhov no tau piav qhia los ntawm qhov kev txiav txim ntawm hluav taws xob tam sim no, photons ntawm lub teeb ntawm cov hlau ions, nyob rau hauv lub zog ntawm cov atoms zoo siab, thiab cov electrons hauv lawv "dhia" mus rau qib siab zog thiab rov qab mus rau lawv qhov chaw nyob ruaj khov. Nws yog vim li no uas lanthanides thiab actinides raug cais ua phosphor.
Qhov tshwm sim ntawm kev txo qis ionic radii ntawm atoms
Nyob rau hauv lanthanum thiab actinium, nrog rau cov ntsiab lus ntawm lawv tsev neeg, muaj ib qho kev txo qis hauv tus nqi ntawm cov ntsuas ntawm radii ntawm hlau ions. Hauv chemistry, nyob rau hauv cov xwm txheej zoo li no nws yog ib txwm hais txog lanthanide thiab actinide compression. Nyob rau hauv chemistry, cov qauv hauv qab no tau tsim: nrog rau kev nce nqi ntawm cov nucleus ntawm atoms, yog tias cov khoom nyob rau tib lub sijhawm, lawv cov radii txo. Qhov no tuaj yeem piav qhia raws li hauv qab notxoj kev: rau cov hlau xws li cerium, praseodymium, neodymium, tus naj npawb ntawm lub zog hauv lawv cov atoms tsis hloov pauv thiab sib npaug rau rau. Txawm li cas los xij, tus nqi ntawm cov nuclei feem ntau nce los ntawm ib qho thiab yog +58, +59, +60. Qhov no txhais tau hais tias lub zog ntawm attraction ntawm cov electrons ntawm lub puab plhaub mus rau qhov zoo nqi nucleus nce. Yog li ntawd, atomic radii txo. Nyob rau hauv ionic compounds ntawm hlau, nrog ib tug nce nyob rau hauv lub atomic tooj, lub ionic radii kuj txo. Cov kev hloov zoo sib xws tau pom hauv cov ntsiab lus ntawm tsev neeg anemone. Yog li ntawd, lanthanides thiab actinides hu ua ntxaib. Kev txo qis hauv radii ntawm ions ua rau, ua ntej ntawm tag nrho cov, mus rau qhov tsis muaj zog ntawm cov yam ntxwv ntawm cov hydroxides Ce(OH) 3, Pr(OH) 3 khoom.
Kev sau ntawm 4f-sublevel nrog cov khoom siv hluav taws xob tsis sib xws mus txog ib nrab ntawm lub orbitals ntawm europium atom ua rau cov txiaj ntsig tsis tau xav txog. Nws lub vojvoog atomic tsis txo qis, tab sis, ntawm qhov tsis sib xws, nce. Gadolinium, uas ua raws li nws nyob rau hauv lub series ntawm lanthanides, muaj ib tug electron nyob rau hauv lub 4f sublevel ntawm 5d sublevel, zoo ib yam li Eu. Cov qauv no ua rau txo qis hauv lub vojvoog ntawm gadolinium atom. Ib qho xwm txheej zoo sib xws tau pom nyob rau hauv ib khub ntawm ytterbium - lutetium. Rau thawj lub caij, lub vojvoog atomic loj yog qhov ua tiav ntawm 4f sublevel, thaum rau lutetium nws txo qis, txij li qhov pom ntawm electrons tau pom ntawm 5d sublevel. Nyob rau hauv actinium thiab lwm yam xov tooj cua ntawm tsev neeg no, lub radii ntawm lawv cov atoms thiab ions tsis hloov monotonously, tab sis, zoo li lanthanides, stepwise. Yog li, lanthanides thiabactinides yog cov ntsiab lus uas nws cov khoom ntawm lawv cov tebchaw sib raug zoo nyob ntawm lub vojvoog ionic thiab cov qauv ntawm lub plhaub hluav taws xob ntawm atoms.
Valence xeev
Lanthanides thiab actinides yog cov khoom uas nws cov yam ntxwv zoo sib xws. Tshwj xeeb, qhov no cuam tshuam rau lawv cov oxidation xeev hauv ions thiab valency ntawm atoms. Piv txwv li, thorium thiab protactinium, uas nthuav tawm qhov valence ntawm peb, nyob rau hauv cov compounds Th(OH)3, PaCl3, ThF. 3, Pa2(CO3)3. Tag nrho cov tshuaj no yog insoluble thiab muaj tib yam tshuaj muaj zog xws li hlau los ntawm tsev neeg lanthanum: cerium, praseodymium, neodymium, thiab lwm yam. Cov lanthanides nyob rau hauv cov tebchaw no kuj yuav trivalent. Cov piv txwv no ib zaug ua pov thawj rau peb qhov tseeb ntawm cov lus hais tias lanthanides thiab actinides yog ntxaib. Lawv muaj lub cev thiab tshuaj lom neeg zoo sib xws. Qhov no tuaj yeem piav qhia feem ntau los ntawm cov qauv ntawm electron orbitals ntawm lub atoms ntawm ob tsev neeg ntawm kev hloov pauv sab hauv.
Metal properties
Txhua tus neeg sawv cev ntawm ob pawg yog hlau, uas 4f-, 5f-, thiab d-sublevels tiav. Lanthanum thiab cov khoom ntawm nws tsev neeg hu ua lub ntiaj teb tsis tshua muaj. Lawv cov yam ntxwv ntawm lub cev thiab tshuaj lom neeg yog nyob ze heev uas lawv tau sib cais nyob rau hauv cov chaw kuaj mob uas nyuaj heev. Feem ntau feem ntau nthuav tawm lub xeev oxidation ntawm +3, cov ntsiab lus ntawm lanthanum series muaj ntau yam zoo sib xws nrog alkaline ntiaj teb hlau (barium, calcium, strontium). Actinides kuj yog cov hlau uas muaj zog heev, thiab tseem muaj xov tooj cua.
Cov yam ntxwv ntawm lanthanides thiab actinides kuj muaj feem xyuam rau cov khoom xws li, piv txwv li, pyrophoricity nyob rau hauv lub xeev zoo dispersed. Kev txo qis ntawm qhov loj ntawm lub ntsej muag-centered crystal lattices ntawm cov hlau kuj tau pom. Peb ntxiv hais tias tag nrho cov tshuaj ntawm ob tsev neeg yog hlau nrog ib tug silvery sheen, vim lawv siab reactivity, lawv sai sai darken nyob rau hauv cov huab cua. Lawv tau them nrog ib zaj duab xis ntawm cov oxide sib raug, uas tiv thaiv oxidation ntxiv. Tag nrho cov ntsiab lus muaj txaus refractory, tshwj tsis yog cov nepunium thiab plutonium, nws cov ntsiab lus melting yog qis dua 1000 ° C.
Tus yam ntxwv tshuaj tiv thaiv
Raws li tau sau tseg ua ntej, lanthanides thiab actinides yog cov hlau ua haujlwm. Yog li, lanthanum, cerium thiab lwm yam khoom ntawm tsev neeg tau yooj yim ua ke nrog cov khoom yooj yim - halogens, nrog rau phosphorus, carbon. Cov lanthanides tuaj yeem cuam tshuam nrog ob qho tib si carbon monoxide thiab carbon dioxide. Lawv kuj muaj peev xwm decomposing dej. Ntxiv rau cov ntsev yooj yim, xws li SeCl3 lossis PrF3, piv txwv li, lawv tsim cov ntsev ob. Hauv kev tshuaj ntsuam chemistry, cov tshuaj tiv thaiv ntawm lanthanide hlau nrog aminoacetic thiab citric acids nyob hauv qhov chaw tseem ceeb. Cov sib xyaw ua ke tsim los ntawm cov txheej txheem zoo li no yog siv los cais cov sib xyaw ntawm lanthanides, piv txwv li, hauv ores.
Thaum cuam tshuam nrog nitrate, chloride thiab sulfate acids, hlautsim cov ntsev sib xws. Lawv yog cov heev soluble nyob rau hauv dej thiab yooj yim muaj peev xwm tsim crystalline hydrates. Nws yuav tsum tau muab sau tseg tias aqueous daws ntawm lanthanide ntsev yog xim, uas yog piav qhia los ntawm lub xub ntiag ntawm cov coj ions nyob rau hauv lawv. Kev daws ntawm samarium lossis praseodymium ntsev yog ntsuab, neodymium - liab-violet, promethium thiab europium - liab. Txij li thaum ions nrog lub xeev oxidation ntawm +3 yog xim, qhov no yog siv nyob rau hauv analytical chemistry kom paub txog lanthanide hlau ions (yog li hu ua qualitative tshua). Rau tib lub hom phiaj, kev tshuaj xyuas tshuaj xws li fractional crystallization thiab ion-exchange chromatography kuj tseem siv.
Actinides tuaj yeem muab faib ua ob pawg ntawm cov ntsiab lus. Cov no yog berkelium, fermium, mendelevium, nobelium, lawrencium thiab uranium, neptunium, plutonium, omercium. Cov khoom siv tshuaj lom neeg ntawm thawj ntawm cov no zoo ib yam li lanthanum thiab hlau los ntawm nws tsev neeg. Cov ntsiab lus ntawm pawg thib ob muaj cov yam ntxwv zoo sib xws (yuav luag zoo ib yam). Tag nrho cov actinides cuam tshuam nrog cov hlau tsis muaj hlau: sulfur, nitrogen, carbon. Lawv tsim cov tebchaw sib xyaw nrog cov lus dab neeg uas muaj oxygen. Raws li peb tuaj yeem pom, cov hlau ntawm ob tsev neeg nyob ze rau ib leeg hauv kev coj tus cwj pwm. Qhov no yog vim li cas cov lanthanides thiab actinides feem ntau hu ua cov hlau ntxaib.
Txoj haujlwm nyob rau hauv lub sijhawm ntawm hydrogen, lanthanides, actinides
Nws yuav tsum tau coj mus rau hauv tus account qhov tseeb tias hydrogen yog ib yam khoom muaj txiaj ntsig zoo. Nws manifests nws tus kheej nyob ntawm tej yam kev mob ntawm cov tshuaj tiv thaiv: ob qho tib si raws li ib tug txo tus neeg sawv cev thiab raws li ib tug oxidizing neeg sawv cev. Yog vim li cas nyob rau hauv lub periodic systemhydrogen nyob ib txhij nyob rau hauv lub ntsiab subgroups ntawm ob pawg ib zaug.
Hauv thawj zaug, hydrogen ua lub luag haujlwm ntawm tus neeg sawv cev txo qis, zoo li cov hlau alkali nyob ntawm no. Qhov chaw ntawm hydrogen nyob rau hauv pawg 7th, nrog rau cov ntsiab lus halogens, qhia nws txo qis peev xwm. Nyob rau hauv lub thib rau lub sij hawm, raws li twb tau hais lawm, lanthanide tsev neeg nyob, muab tso rau hauv ib tug nyias muaj nyias ib kab rau qhov yooj yim thiab compactness ntawm lub rooj. Lub sijhawm xya muaj ib pawg ntawm cov khoom siv hluav taws xob zoo sib xws hauv cov yam ntxwv rau actinium. Actinides nyob rau sab nraum lub rooj ntawm cov tshuaj ntawm DI Mendeleev nyob rau hauv kab ntawm lanthanum tsev neeg. Cov ntsiab lus no yog qhov tsawg tshaj plaws kawm, vim hais tias cov nuclei ntawm lawv cov atoms tsis ruaj tsis khov heev vim yog radioactivity. Nco qab tias lanthanides thiab actinides yog cov hloov pauv sab hauv, thiab lawv cov yam ntxwv physicochemical yog ze rau ib leeg.
Txoj hauv kev tsim cov hlau hauv kev lag luam
Nrog rau kev zam ntawm thorium, protactinium thiab uranium, uas yog mined ncaj qha los ntawm ore, tus so ntawm cov actinides tuaj yeem tau los ntawm irradiating cov qauv ntawm cov hlau uranium nrog ceev nrooj neutron kwj. Ntawm qhov ntsuas kev lag luam, neptunium thiab plutonium yog mined los ntawm siv roj los ntawm nuclear reactors. Nco ntsoov tias kev tsim cov actinides yog cov txheej txheem nyuaj thiab kim, cov txheej txheem tseem ceeb ntawm kev sib pauv ion thiab ntau theem kev rho tawm. Lanthanides, uas yog hu ua cov ntsiab lus tsis tshua muaj hauv ntiaj teb, tau txais los ntawm electrolysis ntawm lawv cov chlorides lossis fluorides. Txoj kev metallothermic yog siv los rho tawm ultrapure lanthanides.
Qhov kev hloov pauv sab hauv yog siv
Kev siv cov hlau peb kawm yog qhov dav heev. Rau tsev neeg anemone, qhov no yog, ua ntej ntawm tag nrho cov, riam phom nuclear thiab lub zog. Actinides kuj tseem ceeb hauv cov tshuaj, tshuaj xyuas qhov tsis haum, thiab kev tshuaj xyuas ua kom muaj zog. Nws yog tsis yooj yim sua kom tsis quav ntsej txog kev siv lanthanides thiab actinides ua qhov chaw ntawm neutron capture nyob rau hauv nuclear reactors. Lanthanides kuj tseem siv los ua alloying ntxiv rau cam khwb cia hlau thiab hlau, nrog rau kev tsim cov phosphor.
Spread in nature
Oxides ntawm actinides thiab lanthanides feem ntau hu ua zirconium, thorium, yttrium earths. Lawv yog lub hauv paus tseem ceeb kom tau txais cov khoom sib xws. Uranium, ua tus sawv cev tseem ceeb ntawm actinides, muaj nyob rau hauv txheej txheej ntawm lithosphere nyob rau hauv daim ntawv ntawm plaub hom ores los yog minerals. Ua ntej tshaj plaws, nws yog uranium pitch, uas yog uranium dioxide. Nws muaj cov ntsiab lus hlau siab tshaj plaws. Feem ntau uranium dioxide yog nrog los ntawm radium deposits (veins). Lawv muaj nyob rau hauv Canada, Fabkis, Zaire. Cov complexes ntawm thorium thiab uranium ores feem ntau muaj cov ores ntawm lwm cov hlau tseem ceeb, xws li kub lossis nyiaj.
Cov khoom khaws cia ntawm cov khoom siv raw yog nplua nuj nyob hauv Russia, South Africa, Canada thiab Australia. Qee cov pob zeb sedimentary muaj cov ntxhia carnotite. Ntxiv nrog rau uranium, nws kuj muaj vanadium. Plaubhom uranium raw khoom yog phosphate ores thiab hlau-uranium shales. Lawv cov peev txheej nyob hauv Morocco, Sweden thiab Asmeskas. Tam sim no, kev tso nyiaj ntawm lignite thiab thee uas muaj uranium impurities kuj suav hais tias muaj kev vam meej. Lawv tau mined hauv Spain, Czech koom pheej, thiab tseem nyob hauv ob lub xeev Asmeskas - North thiab South Dakota.
