Iphethini Yensimbi Ingxenye 3 - Konke Okunye
Okuqukethwe
Ngemuva kwe-lithium, esetshenziswa kakhulu emnothweni wesimanje, kanye ne-sodium ne-potassium, okuphakathi kwezinto ezibaluleke kakhulu embonini nasemhlabeni ophilayo, isikhathi sesifikile sazo zonke ezinye izakhi ze-alkali. Ngaphambi kwethu kukhona i-rubidium, i-cesium ne-franc.
Izakhi ezintathu zokugcina zifana kakhulu komunye nomunye, futhi ngesikhathi esifanayo zinezakhiwo ezifanayo ne-potassium futhi kanye nayo zakha iqembu elincane elibizwa ngokuthi i-potassium. Njengoba cishe ngokuqinisekile ngeke ukwazi ukwenza noma yiziphi izivivinyo nge-rubidium ne-cesium, kufanele ukwaneliswe ngolwazi lokuthi zisabela njenge-potassium nokuthi izinhlanganisela zazo zinokuncibilika okufanayo nezinhlanganisela zayo.
1. Obaba be-spectroscopy: URobert Wilhelm Bunsen (1811-99) kwesobunxele, uGustav Robert Kirchhoff (1824-87) kwesokudla
Intuthuko yokuqala ku-spectroscopy
Isenzo sokufakwa kwemibala kwelangabi ngezinhlanganisela zezakhi ezithile saziwa futhi sisetshenziswa ekwenziweni kweziqhumane kudala ngaphambi kokuthi zikhishelwe esimweni esikhululekile. Ekuqaleni kwekhulu leshumi nesishiyagalolunye, ososayensi bahlola imigqa ye-spectral evela ekukhanyeni kweLanga futhi ikhishwa yizinhlanganisela zamakhemikhali ezishisayo. Ngo-1859, izazi zefiziksi ezimbili zaseJalimane - Robert Bunsen i Gustav Kirchhoff – wakha idivaysi yokuhlola ukukhanya okukhiqiziwe (1). I-spectroscope yokuqala yayinomklamo olula: yayihlanganisa iprism eyayihlukanisa ukukhanya kube imigqa ye-spectral futhi i-eyepiece ene-lens ukuze bakubone (2). Ukuba wusizo kwe-spectroscope ekuhlaziyeni amakhemikhali kwaqashelwa ngokushesha: into ihlukana ibe ama-athomu ekushiseni okuphezulu komlilo, futhi le migqa ikhipha imigqa engokwayo kuphela.
2. G. Kirchhoff ku-spectroscope
3. I-Metallic cesium (http://images-of-elements.com)
UBunsen noKirchhoff baqala ucwaningo lwabo kwathi ngemva konyaka bahwamuka amathani angama-44 amanzi amaminerali esiphethwini saseDurkheim. Imigqa ivele ku-spectrum ye-sediment eyayingenakubalulwa kunoma iyiphi into eyaziwa ngaleso sikhathi. U-Bunsen (naye wayengusokhemisi) wahlukanisa i-chloride yesici esisha esitshalweni, futhi wanikeza igama lensimbi equkethwe kuyo. NGENXA ngokusekelwe emigqeni eluhlaza okwesibhakabhaka eqinile ku-spectrum yayo (Latin = blue) (3).
Ezinyangeni ezimbalwa kamuva, kakade ngo-1861, ososayensi bahlola i-spectrum yediphozi kasawoti ngokuningiliziwe futhi bathola ukuba khona kwesinye isici kuwo. Bakwazi ukuhlukanisa i-chloride yayo futhi banqume ubukhulu bayo be-athomu. Njengoba imigqa ebomvu yayibonakala ngokucacile ku-spectrum, insimbi entsha ye-lithium yaqanjwa rubid (kusuka kusiLatini = okubomvu okumnyama) (4). Ukutholakala kwezinto ezimbili ngokuhlaziywa kwe-spectral kwaqinisekisa osokhemisi nezazi zefiziksi. Eminyakeni eyalandela, i-spectroscopy yaba elinye lamathuluzi okucwaninga ayinhloko, futhi okwatholwa kwana njenge-cornucopia.
4. I-rubidium yensimbi (http://images-of-elements.com)
I-Rubid ayiwakhi amaminerali ayo, futhi i-cesium yinye kuphela (5). Zombili izakhi. Ungqimba olungaphezulu loMhlaba luqukethe i-rubidium engu-0,029% (indawo ye-17 ohlwini lwama-elemental abundances) kanye ne-0,0007% ye-cesium (indawo engu-39). Akuwona ama-bioelements, kodwa ezinye izitshalo zikhetha ukukhetha i-rubidium, njengogwayi namabhitrudi. Ngokombono we-physicochemical, zombili izinsimbi "ziyi-potassium kuma-steroids": zithambile futhi zi-fusible, futhi zisebenza kakhulu (ngokwesibonelo, zivutha ngokuzenzekelayo emoyeni, futhi zisabela ngisho namanzi ngokuqhuma).
ngokusebenzisa iyisici "esansimbi" kunazo zonke (ekhemikhali, hhayi ngomqondo wokuxoxisana wegama). Njengoba kushiwo ngenhla, izakhiwo zezinhlanganisela zabo nazo zifana nalezo ze-potassium compounds ezifanayo.
5. I-Pollucite ukuphela kwezimbiwa ze-cesium (USGS)
i-rubidium yensimbi futhi i-cesium itholakala ngokunciphisa izinhlanganisela zazo ne-magnesium noma i-calcium endaweni engenalutho. Njengoba zidingeka kuphela ukukhiqiza izinhlobo ezithile zamaseli elanga (ukukhanya kwesigameko kukhipha kalula ama-electron ezindaweni zawo), ukukhiqizwa konyaka kwe-rubidium ne-cesium ku-oda lamakhulu amakhilogremu. Izinhlanganisela zabo nazo azisetshenziswa kakhulu.
Njenge-potassium, enye ye-isotopes ye-rubidium i-radioactive. I-Rb-87 inengxenye yempilo yeminyaka eyizigidi eziyizinkulungwane ezingama-50, ngakho-ke imisebe iphansi kakhulu. Le isotope isetshenziselwa ama-date rocks. I-Cesium ayinawo ama-isotopes emisebe eyenzeka ngokwemvelo, kodwa CS-137 ingenye yemikhiqizo yokuqhekeka kwe-uranium kuma-reactors enuzi. Ihlukaniswe nezinduku zikaphethiloli ezisetshenzisiwe ngoba le isotopu yasetshenziswa njengomthombo we-g-radiation, isibonelo, ukucekela phansi izimila ezinomdlavuza.
Ngokuhlonishwa kweFrance
6. Umsunguli wolimi lwesiFulentshi - uMarguerite Perey (1909-75)
UMendeleev wayesekubone kusengaphambili ukuthi kukhona i-lithium metal esindayo kune-cesium futhi wayinika igama elisebenzayo. Osokhemisi bayifune kwamanye amaminerali e-lithium ngoba, njengesihlobo sabo, kufanele ibe khona. Izikhathi eziningana kwakubonakala sengathi itholwe, nakuba icatshangwa, kodwa ayizange yenzeke.
Ekuqaleni kwawo-87, kwaba sobala ukuthi isici sika-1914 sasinomsakazo. Ngo-227, izazi ze-physics zase-Austria zase ziseduze nokuthola. U-S. Meyer, W. Hess, kanye no-F. Panet babone ukuphuma kwe-alpha okubuthakathaka ekulungiselelweni kwe-actinium-89 (ngaphezu kwezinhlayiya ze-beta ezifihliwe kakhulu). Njengoba inombolo ye-athomu ye-actinium ingu-87, futhi ukukhishwa kwezinhlayiya ze-alpha kungenxa "yokwehliswa" kwe-elementi ezindaweni ezimbili kuthebula le-periodic, isotopu enenombolo ye-athomu engu-223 kanye nenombolo ye-athomu engu-XNUMX bekufanele, noma kunjalo, izinhlayiya ze-alpha zamandla afanayo (ububanzi bezinhlayiya ezisemoyeni bulinganiswa ngokulinganayo amandla azo) futhi ithumela i-isotope ye-protactinium, abanye ososayensi baye basikisela ukungcoliswa komuthi.
Ngokushesha kwagqashuka impi futhi konke kwalibaleka. Ngawo-30, ama-accelerator ezinhlayiyana aklanywa futhi izakhi zokuqala zokwenziwa zatholwa, njenge-astatium eyayilindelwe isikhathi eside enenombolo ye-athomu 85. Endabeni yesici 87, izinga lobuchwepheshe langaleso sikhathi alizange livumele ukuthola inani elidingekayo le-athomu. impahla for synthesis. Isazi sefiziksi esingumFulentshi saphumelela kungazelelwe UMarguerite Perey, umfundi kaMaria Sklodowska-Curie (6). Yena, njengabase-Austrians engxenyeni yesine yekhulu edlule, wafunda ukubola kwe-actinium-227. Inqubekelaphambili yezobuchwepheshe yenza kwaba nokwenzeka ukuthola ukulungiswa okumsulwa, futhi kulokhu akekho owayenokungabaza ukuthi wayesekhonjiwe ekugcineni. Umhloli wamqamba igama french ngokuhlonipha izwe lakubo. I-Element 87 yaba ngeyokugcina ukutholwa kumaminerali, okwalandela kwatholakala ngokuzenzela.
Frans kwakheka egatsheni elihlangothini lochungechunge lwe-radioactive, ngenqubo esebenza kahle kakhulu futhi, ngaphezu kwalokho, luhlala isikhathi esifushane kakhulu. I-isotopu enamandla kunazo zonke etholwe nguNkk. Perey, Fr-223, inengxenye yempilo engaphezudlwana nje kwemizuzu engu-20 (okusho ukuthi 1/8 kuphela yenani lokuqala elisele ngemva kwehora). Kubalwe ukuthi imbulunga yonke iqukethe kuphela amagremu angu-30 e-franc (ukulingana kuyasungulwa phakathi kwe-isotope ebolayo kanye ne-isotope esanda kwakhiwa).
Nakuba ingxenye ebonakalayo ye-franc compounds ayizange itholakale, izakhiwo zayo zafundwa, futhi kwatholakala ukuthi ziyingxenye yeqembu le-alkali. Isibonelo, lapho i-perchlorate yengezwa kwisisombululo esiqukethe i-franc ne-potassium ions, imvula izoba yi-radioactive, hhayi isisombululo. Lokhu kuziphatha kufakazela ukuthi i-FrClO4 inyibilika kancane (igxuma nge-KClO4), futhi izakhiwo ze-francium ziyefana nalezo ze-potassium.
France, wayezoba kanjani...
… Uma ngingathola isampula layo elibonakalayo ngeso lenyama? Yiqiniso, ithambile njengengcina, futhi mhlawumbe enombala osagolide (i-cesium engenhla ithambile futhi iphuzi ngombala). Izoncibilika ku-20-25°C futhi ihwamuke cishe ku-650°C (isilinganiso sisekelwe kudatha yesiqephu sangaphambilini). Ngaphezu kwalokho, izosebenza kakhulu ngamakhemikhali. Ngakho-ke, kufanele igcinwe ngaphandle kokuthola umoya-mpilo nomswakama kanye nesitsha esivikela emisebeni. Kuzodingeka ukusheshisa ukuhlolwa, ngoba emahoreni ambalwa ngeke kube khona isiFulentshi esisele.
I-lithium ehloniphekile
Khumbula ama-pseudo-halogens avela kumjikelezo we-halogen wangonyaka odlule? Lawa ama-ion aziphatha njengama-anion afana no-Cl- noma cha-. Lokhu kufaka phakathi, isibonelo, i-cyanides CN- kanye nezinhlayiya ze-SCN-, ukwakha usawoti onokuncibilika okufana nalokhu kweqembu le-anions le-17.
Abantu baseLithuania nabo banomlandeli, okuyi-ammonium ion NH. 4 + – umkhiqizo wokuncibilika kwe-ammonia emanzini (isixazululo se-alkaline, nakuba sibuthakathaka kunesimo se-alkali metal hydroxides) kanye nokusabela kwayo ngama-asidi. I-ion isabela ngendlela efanayo nezinsimbi ze-alkali esindayo, futhi ukuhlobana kwayo okuseduze kune-potassium, isibonelo ifana ngosayizi we-potassium cation futhi ivamise ukuthatha indawo ye-K+ ezinhlanganisela zayo zemvelo. Izinsimbi ze-lithium zisebenza kakhulu ukuthi zingakhiqizwa yi-electrolysis yezixazululo ezinamanzi zikasawoti nama-hydroxides. Ukusebenzisa i-mercury electrode, isisombululo sensimbi ku-mercury (i-amalgam) sitholakala. I-ammonium ion ifana kakhulu nezinsimbi ze-alkali kangangokuthi iphinde yakhe i-amalgam.
Enkambweni ehlelekile yokuhlaziywa kwe-L.izinto ze-magnesium ion ngezokugcina ukutholwa. Isizathu ukuncibilika okuhle kwama-chloride, ama-sulfate nama-sulfide, okusho ukuthi awadli ngaphansi kwesenzo sama-reagents angezwe ngaphambilini asetshenziselwa ukunquma ukuba khona kwezinsimbi ezisindayo kusampula. Nakuba usawoti we-ammonium nawo uncibilika kakhulu, utholwa ekuqaleni kokuhlaziywa, ngoba akakwazi ukumelana nokushisa nokuhwamuka kwezixazululo (abola kalula lapho kukhishwa i-ammonia). Inqubo cishe yaziwa yiwo wonke umuntu: isixazululo sesisekelo esiqinile (NaOH noma i-KOH) sengezwe kusampula, esibangela ukukhululwa kwe-ammonia.
Sam i-ammonia itholwa ngephunga noma ngokufaka ucezu lwephepha lomhlaba wonke oluswakanyiswe ngamanzi entanyeni yeshubhu lokuhlola. NH igesi3 incibilika emanzini futhi yenze isixazululo sibe ne-alkali futhi iphendule iphepha libe luhlaza okwesibhakabhaka.
7. Ukutholwa kwama-ammonium ion: kwesokunxele umugqa wokuhlola uphenduka ube luhlaza okwesibhakabhaka ngaphansi kwethonya le-ammonia ekhishwe, kwesokudla - umphumela omuhle wokuhlolwa kwe-Nessler
Lapho uthola i-ammonia ngosizo lwephunga, kufanele ukhumbule imithetho yokusebenzisa ikhala elabhorethri. Ngakho-ke, unganciki phezu komkhumbi wokusabela, qondisa imfucumfucu ibheke kuwe ngokunyakazisa abalandeli besandla sakho futhi ungawuholeli umoya "isifuba esigcwele", kodwa vumela iphunga lenhlanganisela lifinyelele ekhaleni lakho ngokwalo.
Ukuncibilika kosawoti we-ammonium kufana nalokhu kwezinhlanganisela ze-potassium ezifanayo, ngakho-ke kungase kulinge ukulungisa i-ammonium perchlorate NH.4I-ClO4 kanye nenhlanganisela eyinkimbinkimbi ene-cobalt (imininingwane, bheka isiqephu sangaphambilini). Kodwa-ke, izindlela eziveziwe azifanelekile ukuthola amanani amancane kakhulu e-ammonia ne-ammonium ion kusampula. Kulabhorethri, i-reagent ka-Nessler isetshenziselwa le njongo, eginqika noma iguqule umbala ngisho nalapho kukhona iminonjana ye-NH.3 (7).
Kodwa-ke, ngeluleka ngokuqinile ngokumelene nokwenza ukuhlolwa okufanele ekhaya, njengoba kudingekile ukusebenzisa izinhlanganisela ezinobuthi ze-mercury.
Linda uze ube elabhorethri yobungcweti ngaphansi kokuqondisa kochwepheshe bomeluleki. I-Chemistry iyathakazelisa, kodwa - kulabo abangazi noma abanganaki - ingaba yingozi.
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