Labo akha usawoti, ingxenye 4 Bromine

Esinye isici esivela emndenini we-halogen yi-bromine. Ithatha indawo phakathi kwe-chlorine ne-iodine (kanye yakha i-halogen subfamily), futhi izakhiwo zayo ziyisilinganiso uma iqhathaniswa nomakhelwane bayo phezulu nangaphansi kweqembu. Nokho, noma ubani ocabanga ukuthi lesi isici esingathandeki uyokwenza iphutha.

Isibonelo, i-bromine iwukuphela koketshezi phakathi kwezinto ezingezona izinsimbi, futhi umbala wayo nawo uhlala uhlukile emhlabeni wezakhi. Into eyinhloko, nokho, ukuthi ukuhlolwa okuthakazelisayo kungenziwa ngakho ekhaya.

- Kukhona okunuka kabi lapha! -

...... kubabaza usokhemisi ongumFulentshi UJoseph Gay-Lussaclapho ehlobo lika-1826, egameni le-French Academy, wahlola umbiko ngokutholakala kwesici esisha. Umbhali wayo wayengaziwa kabanzi Antoine Izingane. Ngonyaka odlule, usokhemisi oneminyaka engu-23 ubudala wayephenya ukuthi kungenzeka yini ukuthola i-iodine ekukhiqizeni izixazululo ezisele ekuhlanganiseni kukasawoti wamatshe emanzini olwandle (indlela esetshenziselwa ukuthola usawoti ezindaweni ezifudumele ezifana nogu lwaseMedithera yaseFrance). I-chlorine yagcwala isixazululo, ikhipha i-iodine kusawoti wayo. Wathola isici, kodwa waphawula enye into - ifilimu yoketshezi oluphuzi olunephunga elinamandla. Wawuhlukanisa wabe esewuhlanganisa. Insalela yayiwuketshezi olunsundu ngokumnyama olungafani nanoma iyiphi into eyaziwayo. Imiphumela yokuhlolwa kuka-Balar ibonise ukuthi lena into entsha. Ngakho-ke, wathumela umbiko e-French Academy futhi walinda isinqumo sayo. Ngemva kokuqinisekiswa kokutholakala kuka-Balar, kwahlongozwa igama lesici i-bromine, ethathwe kwelesiGreki elithi bromos, i.e. iphunga, ngoba iphunga le-bromine alimnandi (1).

Ukuqapha Iphunga elibi akuyona ukuphela kobubi be-bromine. Lesi sici siyingozi njengama-halogens aphezulu, futhi, uma sesikhumbeni, sishiya amanxeba okunzima ukuwapholisa. Ngakho-ke, kungakhathaliseki ukuthi kufanele uthole i-bromine ngendlela ehlanzekile futhi ugweme ukuhogela iphunga lesixazululo sayo.

amanzi olwandle element

Amanzi olwandle aqukethe cishe yonke i-bromine ekhona emhlabeni. Ukuchayeka ku-chlorine kubangela ukukhululwa kwe-bromine, eshintshashintsha emoyeni osetshenziselwa ukuvuthela amanzi. Ku-receiver, i-bromine iyafinyezwa bese ihlanjululwa nge-distillation. Ngenxa yokuncintisana eshibhile kanye nokusebenza kabusha okuncane, i-bromine isetshenziswa kuphela uma idingeka. Izinto eziningi ezisetshenziswayo azisekho, njenge-bromide esiliva ekuthwebuleni izithombe, izithasiselo zikaphethiloli onomthofu, nezinto zokucima umlilo ze-halon. I-Bromine iyingxenye yamabhethri e-bromine-zinc, futhi izinhlanganisela zayo zisetshenziswa njengezidakamizwa, odayi, izithasiselo zokunciphisa ukuvutha kwamapulasitiki, nemikhiqizo yokuvikela izitshalo.

Ngamagama amakhemikhali, i-bromine ayihlukile kwamanye ama-halogen: yenza i-hydrobromic acid eqinile HBr, usawoti one-anion ye-bromine namanye ama-acids oksijini nosawoti wawo.

Umhlaziyi we-Bromine

Izici zokusabela ze-bromide anion ziyefana nokuhlolwa okwenziwa ngama-chloride. Ngemva kokwengeza isixazululo sesiliva nitrate AgNO₃ imvula engancibiliki kahle ye-AgBr, iba mnyama ekukhanyeni ngenxa yokubola kwekhemikhali. Imvula inombala ophuzi (ngokungafani ne-AgCl emhlophe kanye ne-AgI ephuzi) futhi ayincibiliki kahle lapho isixazululo se-NH ammonia sengezwa._3aq (okuyihlukanisa ku-AgCl, encibilika kakhulu ngaphansi kwalezi zimo) (2). 

2. Ukuqhathaniswa kwemibala ye-halide yesiliva - ukubola kwabo ngemva kokuchayeka ekukhanyeni kubonakala ngezansi.

Indlela elula yokuthola ama-bromide ukuwenza i-oxidize futhi unqume ubukhona be-bromine yamahhala. Ukuhlolwa uzodinga: potassium bromide KBr, potassium permanganate KMnO₄, isisombululo se-sulfuric acid (VI) H₂SO₄ kanye ne-organic solvent (isb., okokunciphisa upende). Thela inani elincane lezixazululo ze-KBR ne-KMnO eshubhuni yokuhlola.₄bese kuba namaconsi ambalwa e-asidi. Okuqukethwe ngokushesha kuba phuzi (ekuqaleni kwakunsomi ku-potassium permanganate eyengeziwe):

2KМно₄ +10KBr +8H₂SO4 → 2MnSO₄ + 6 izinkulungwane₂SO₄ +5Br₂ + 8 amahora₂Mayelana nokungeza ukuphakela

3. Ibromine ekhishwe ongqimbeni olunamanzi (phansi) inemibala ungqimba lwe-organic solvent ngokubomvu-nsundu (phezulu).

i-solvent bese unyakazisa i-vial ukuxuba okuqukethwe. Ngemva kokuhlubuka, uzobona ukuthi ungqimba lwe-organic luthathe umbala obomvu onsundu. I-Bromine incibilika kangcono oketshezini olungezona e-polar futhi isuka emanzini iye kwincibilikisi. Umkhuba obhekiwe inkunzi (3). 

Amanzi e-bromine ekhaya

amanzi e-bromine iyisisombululo esinamanzi esitholakala ezimbonini ngokuncibilikisa i-bromine emanzini (cishe u-3,6 g we-bromine nge-100 g yamanzi). Kuyi-reagent esetshenziswa njenge-ejenti e-oxidizing emnene futhi ukuthola imvelo engagcwalisiwe yezinhlanganisela eziphilayo. Kodwa-ke, i-bromine yamahhala iyinto eyingozi, futhi ngaphandle kwalokho, amanzi e-bromine akazinzile (i-bromine iyahwamuka esixazululweni bese iphendula ngamanzi). Ngakho-ke, kungcono ukuyithola kancane bese uyisebenzisela ukuhlola.

Usuvele ufunde indlela yokuqala yokuthola ama-bromide: i-oxidation eholela ekwakhekeni kwe-bromine yamahhala. Ngalesi sikhathi, engeza amaconsi ambalwa ka-H kusixazululo se-potassium bromide KBr ku-flask.₂SO₄ kanye nengxenye ye-hydrogen peroxide (3% H₂O₂ esetshenziswa njengesibulala-magciwane). Ngemva kwesikhashana, ingxube iba phuzi:

2KBr+H₂O₂ +H₂SO₄ →K₂SO₄ + Br₂ + 2 amahora₂O

Amanzi e-bromine atholakala ngaleyo ndlela angcolile, kodwa u-X ukuphela kokukhathazeka.₂O₂. Ngakho-ke, kufanele isuswe nge-manganese dioxide MnO.₂ezobolisa i-hydrogen peroxide eyeqile. Indlela elula yokuthola inhlanganisela isuka kumaseli alahlwayo (aqokwe njenge-R03, R06), lapho isesimweni senqwaba emnyama egcwalisa inkomishi ye-zinc. Faka i-pinch ye-mass ku-flask, futhi ngemva kokusabela, uthele i-supernatant, futhi i-reagent isilungile.

Enye indlela i-electrolysis yesisombululo esinamanzi se-KBr. Ukuze uthole isisombululo se-bromine esihlanzekile, udinga ukwakha i-diaphragm electrolyzer, i.e. vele uhlukanise ingilazi ngocezu olufanele lwekhadibhodi (lokhu kuzonciphisa ukuxubana kwemikhiqizo yokusabela kuma-electrode). I-electrode enhle izoba induku yegraphite ethathwe kuseli elilahlwayo 3 eliphawulwe ngenhla, futhi i-electrode engalungile izoba isipikili esivamile. Umthombo wamandla ibhethri yeselula engu-4,5V. Thela isixazululo se-KBr ebhekhani, faka ama-electrode ngezintambo ezinamathiselwe, bese uxhuma ibhethri ezintanjeni. Eduze kwe-electrode ephozithivu isisombululo sizophenduka sibe phuzi (lawa amanzi akho e-bromine), futhi amabhamuza e-hydrogen azokwakheka ku-electrode engemihle (4). Kunephunga elinamandla le-bromine ngaphezu kwengilazi. Dweba isixazululo ngesirinji noma ipayipi.

4. Iseli elenziwe ekhaya le-diaphragm kwesokunxele kanye neseli efanayo ekukhiqizeni amanzi e-bromine (kwesokudla). I-reagent iqoqa eduze kwe-electrode enhle; amabhamuza e-hydrogen ayabonakala ku-electrode engemihle.

Ungagcina amanzi e-bromine isikhathi esifushane esitsheni esivalwe ngokuqinile, esivikelwe ekukhanyeni nasendaweni epholile, kodwa kungcono ukuyizama ngaso leso sikhathi. Uma wenza amaphepha e-starch iodine ngokusho kweresiphi kusukela esigabeni sesibili somjikelezo, faka iconsi lamanzi e-bromine ephepheni. Kuzovela indawo emnyama ngokushesha, ekhombisa ukwakheka kwe-iodine yamahhala:

2KI + Br.₂ → i₂ + KVg

Njengoba nje i-bromine itholakala emanzini olwandle ngokuwasusa kuma-bromide nge-oxidizing ejenti enamandla (), kanjalo ne-bromine isusa i-iodine ibe buthaka kunayo kuma-iodide (Yebo, i-chlorine izophinde isuse iodine).

Uma ungenalo iphepha lesitashi le-iodine, thela isisombululo se-potassium iodide eshubhuni yokuhlola bese wengeza amaconsi ambalwa amanzi e-bromine. Isixazululo siba mnyama, futhi lapho inkomba yesitashi (ukumiswa kukafulawa wamazambane emanzini) ingezwa, iphenduka ibe luhlaza okwesibhakabhaka - umphumela ukhombisa ukubukeka kwe-iodine yamahhala (5). 

5. Ukutholwa kwe-bromine. Ngenhla - iphepha le-iodine-isitashi, ngezansi - isisombululo se-potassium iodide enenkomba yesitashi (ngakwesokunxele - ama-reagents okusabela, ngakwesokudla - umphumela wokuxuba izixazululo).

Izivivinyo ezimbili zasekhishini.

Ezivivinyweni eziningi ngamanzi e-bromine, ngiphakamisa ezimbili ozodinga ngazo ama-reagents avela ekhishini. Okokuqala, khipha ibhodlela lamafutha e-rapeseed,

7. Ukusabela kwamanzi e-bromine ngamafutha yemifino. Ungqimba olungaphezulu lwamafutha luyabonakala (kwesobunxele) kanye nongqimba olungaphansi lwamanzi olungcoliswe i-bromine ngaphambi kokusabela (kwesobunxele). Ngemva kokusabela (kwesokudla), ungqimba olunamanzi luye lwaba nombala.

ubhekilanga noma amafutha omnqumo. Thela inani elincane lamafutha emifino ku-tube yokuhlola ngamanzi e-bromine bese unyakazisa okuqukethwe ukuze ama-reagents ahlangane kahle. Njengoba i-emulsion ye-labile iphuka, amafutha azoba phezulu (ancane kakhulu kunamanzi) futhi amanzi e-bromine aphansi. Nokho, ungqimba lwamanzi lulahlekelwe umbala walo ophuzi. Lo mphumela "wenqabela" isixazululo esinamanzi futhi uyisebenzisela ukusabela ngezingxenye zamafutha (6). 

Amafutha emifino aqukethe inqwaba yama-acids angagcwalisiwe (ahlanganiswe ne-glycerin ukwenza amafutha). Ama-athomu e-Bromine anamathiselwe kuma-double bond kuma-molecule alawa ma-asidi, enze okuphuma ku-bromine okuhambisanayo. Ushintsho embala wamanzi e-bromine luyinkomba yokuthi ama-organic compounds angenayo i-unsaturated akhona kusampula yokuhlola, i.e. izinhlanganisela ezinezibopho ezimbili noma ezintathu phakathi kwama-athomu e-carbon (7). 

Ngokuhlolwa kwesibili kwasekhishini, lungiselela i-baking soda, okungukuthi i-sodium bicarbonate, i-NaHCO.₃, kanye noshukela ababili - i-glucose ne-fructose. Ungathenga i-soda ne-glucose esitolo segrosa, kanye ne-fructose esitolo sesifo sikashukela noma esitolo sokudla sezempilo. I-glucose ne-fructose zakha i-sucrose, okuwushukela ovamile. Ngaphezu kwalokho, zifana kakhulu ezakhiweni futhi zinefomula ephelele efanayo, futhi uma lokhu kwakungenele, zishintsha kalula zibe omunye nomunye. Yiqiniso, kukhona umehluko phakathi kwabo: i-fructose imnandi kune-glucose, futhi ngesisombululo iphendulela indiza yokukhanya kwelinye icala. Kodwa-ke, uzosebenzisa umehluko wesakhiwo samakhemikhali ukuze uhlonzwe: i-glucose iyi-aldehyde futhi i-fructose i-ketone.

7. Ukusabela kokwengezwa kwe-bromine ekubopheni

Ungase ukhumbule ukuthi ukunciphisa ushukela kukhonjwa kusetshenziswa ukuhlolwa kwe-Trommer ne-Tollens. Ukubuka kwangaphandle kwesitini se-Cu deposit₂O (emzamweni wokuqala) noma isibuko sesiliva (kwesibili) sibonisa ukuba khona kokunciphisa ama-compounds, njenge-aldehydes.

Kodwa-ke, le mizamo ayihlukanisi phakathi kwe-glucose aldehyde ne-fructose ketone, ngoba i-fructose izoshintsha ngokushesha ukwakheka kwayo endaweni yokusabela, iphenduke ibe ushukela. Kudingeka i-reagent encane.

Ama-halogens njenge 

Kukhona iqoqo lamakhemikhali amakhemikhali afana nezakhiwo kuma-compounds afanayo. Akha ama-asidi efomula evamile i-HX nosawoti one-mononegative X– anions, futhi lawa ma-asidi awakhiwe ngama-oxide. Izibonelo zama-pseudohalogens anjalo ubuthi obuyi-hydrocyanic acid HCN kanye ne-thiocyanate HSCN engenabungozi. Ezinye zazo zize zakhe ama- molecule e-diatomic, njenge-cyanogen (CN).₂.

Yilapho amanzi e-bromine engena khona. Yenza izixazululo: i-glucose ngokungezwa kwe-NaHCO₃ kanye ne-fructose, kanye nokwengezwa kwe-baking soda. Thela isisombululo se-glucose esilungisiwe kwelinye ishubhu lokuhlola elinamanzi e-bromine, bese kwelinye - isixazululo se-fructose, namanzi e-bromine. Umehluko ubonakala ngokucacile: amanzi e-bromine ashintshe umbala ngaphansi kwethonya lesisombululo se-glucose, kuyilapho i-fructose ingazange ibangele izinguquko. Oshukela ababili bangahlukaniswa kuphela endaweni ene-alkaline kancane (ehlinzekwa yi-sodium bicarbonate) kanye ne-ejenti e-oxidizing emnene, okungukuthi amanzi e-bromine. Ukusetshenziswa kwesisombululo se-alkaline esinamandla (esidingekayo ekuhlolweni kwe-Trommer ne-Tollens) kubangela ukuguqulwa okusheshayo koshukela owodwa kuya komunye kanye nokushintsha umbala wamanzi e-bromine nawo nge-fructose. Uma ufuna ukuthola, phinda ukuhlola usebenzisa i-sodium hydroxide esikhundleni sesoda yokubhaka.