International nokuhlelwa of alkanes. Alkanes: isakhiwo, iimpawu

Kuluncedo ukuba uqale ingcaciso alkanes. Oku Igcwele okanye ifumile hydrocarbon, paraffins. Kwakhona bathi carbons apho ezimbaxa C athom lwenziwa ngendlela yonxulumano ezilula. Le ndlela yokubala jikelele le fom: CnH₂n + 2.

Yinto eyaziwayo ukuba umlinganiselo H no C atom e iimolekyuli zabo kangangoko kunokwenzeka xa kuthelekiswa nezinye iiklasi. Ngenxa yokuba zonke valences zigcwele okanye C, okanye H, kunye neempawu lwemichiza alkanes ngayo ngokuqaqambileyo ngokwaneleyo, ngoko igama lwabo lwesibini kuphuma umda ibinzana okanye hydrocarbon kwizinyibilikisi.

kukho kwakhona igama yamandulo ngakumbi ukuba ungumfanekiso himinertnost kwako - paraffins, Oko kuthetha "eswele ngobuhlobo".

Ngoko ke, isihloko incoko namhlanje wethu: "Alka: homologous series, nokuhlelwa, isakhiwo, isomerism". Ngeke kwakhona data ekhoyo ngokuphathelele iimpawu zomzimba.

Alkanes: isakhiwo, nokuhlelwa

Kwezi atom C zikwimeko efana sp3-hybridization. Ngoko molecule alkane kungaboniswa njenge iseti tetrahedral izakhiwo C, abaqhagamshelwe kuphela phakathi kwawo kodwa H.

Phakathi athom C no H akhoyo ixesha elide, phantsi kakhulu polar s-bond. Atom ngeenxa iibhondi olunye njalo phendula ngenxa alkanes iimolekyuli ngeendlela ezahlukeneyo, apho ubude uxhulumaniso, i-engile ephakathi nazo - constants. Iifomu, ezo similise enye kwenye ngenxa njengokujikeleza molecule, olwenzeka ehlabathini σ-bonds, nezaziwa Ukumila yayo.

Kwinkqubo looding evela H atom kwemolekyuli enza amasuntswana-valent 1 ekuthiwa hydrocarbon radicals. Ezi zinto zibangelwa kuphela khompawundi organic kodwa ezingaphiliyo. Ukuba Khupha ingaphezulu hydrogen ezimbini ukusuka umda ezizizembiwa molecule, omnye ufumana radicals-2-Valence.

Ngaloo alkanes ingaba nokuhlelwa:

• ziqu (uguqulelo oludala);
• Ukwenziwa kwezilungiso (international, ngendlela). Waye obekwa IUPAC.

nokuhlelwa ikakhulu ziqu

Kwimeko yokuqala alkanes nokuhlelwa luphawulwa ngolu hlobo lulandelayo:

1. hydrocarbon Ukuqwalaselwa njengoko avela methane, nto leyo endaweni yi-1 okanye ngaphezulu H atom radicals.
2. Izinga eliphezulu lula kwimeko iikhompawundi hayi sinzima kakhulu.

Iimpawu nokuhlelwa ngokutsha

Ukwenziwa kwezilungiso nokuhlelwa alkane na ezi mpawu zilandelayo:

1. Isiseko igama - 1 kwikhonkco carbon, kunye eseleyo ngamaqhekeza emolekyuli zithathwa nje substituents.
2. Ukuba kukho radicals ezininzi twatse phambi igama labo ibonisa inani (ngokungqongqo amagama), kunye namanani olukhulu wodwa ngeziphumlisi.

Chemistry: nokuhlelwa of alkanes

Ukunenzela lula, ulwazi lunikezelwa ngendlela tabular.

Le alkanes nokuhlelwa ngasentla ziquka amagama ngokwembali ukuyilwa (lekota yokuqala 4 thotho hydrocarbon befumile).

alkanes Apha nondeployed nge-5 okanye ngaphezulu C wabumba lesiGrike neenyumerali athom ezityhila enikiweyo inani athom C. Ngaloo Isimamva -eka ibonisa ukuba ubuncwane eziliqela iikhompawundi kwizinyibilikisi.

Xa ukuzoba izihloko ithumele alkanes njengoko chain eziphambili ukhethe enye equlathe nani liphezulu athom C. kwababaliweyo ukuze substituents kufuneka elona nani lincinane. Kwimeko neentsontelo ezimbini okanye ngaphezulu anobude obulinganayo iba esingundoqo enoku nani liphezulu substituents.

isomerism of alkanes

Njengoko hydrocarbon-ngunozala eziliqela izenzo methane CH₄. Nabamele ngalinye thotho methane waphawula ngokwahlukileyo kwiqela methylene yangaphambili - CH₂. Le ndlela ezaqala kulo imingcelele alkanes.

Isazinzulu German Schill wabeka phambili isindululo igama inani homologous. Iguqulwe kwintsingiselo lesiGrike 'efanayo, ngathi. "

Ngaloo ndlela, la manqaku homologous - iseti ehlobene organic ukuba uhlobo olufanayo lwesakhiwo kunye himsvoystvami n'wina. Homologs - amalungu thotho. umahluko Homologous - iqela methylene ngalo ezimbini homologue ezahlukeneyo ezikufutshane.

Njengoko kukhankanyiwe ngaphambili, kuqamba na ezizizembiwa ifumile ukuze abonise indlela jikelele CnH₂n + 2. Ngenxa yoko, emva methane lilungu thotho homologous ka-methane - C₂H₆. Baphethe isakhiwo methane, kuyimfuneko ukuba indawo atom H kwi-1 CH₃ (mzobo ungezantsi).

Ubume homologue nganye ezilandelayo anokuzuzwa ngasentla ngendlela efanayo. Ngenxa-methane kwakhiwa propane - C₃H₈.

Yintoni isomers?

Ngaba izinto ukuba zibe kuqamba efana ubunjani kunye neenkcukacha zamanani ezinto (twatse ifomula molekyuli) kodwa izakhiwo yemichiza ezahlukeneyo nokuba himsvoystvami ezahlukeneyo.

Lubonakala hydrocarbon ngentla ezinjalo parameter njengoko lobushushu elibilayo: -0,5 ° - butane, -10 ° - isobutane. Olu hlobo isomerism nezaziwa carbon skeleton isomerism, edibana ngayo uhlobo lwesakhiwo.

Inani isomers zolwakhiwo kwanda ngokukhawuleza kunye nenani athom carbon. Ngaloo ndlela, C₁₀H₂₂ ilingane 75 (hayi kuquka isithuba), kwaye 4347 C₁₅H₃₂ isomers isomers sele isaziwa kuba C₂₀H₄₂ - 366.319.

Ngoko sele kwacaca ukuba alkanes, kuthotho homologous, isomerism, nokuhlelwa enjalo. Ngoku kuyimfuneko ukuba uye imithetho amagama IUPAC.

IUPAC nokuhlelwa: Igama kwemfundo

Okokuqala, kuyimfuneko ukuba ukufumana isakhiwo kwitsheyini ezizizembiwa carbon, leyo iqulathe ubude kakhulu kunye nani liphezulu substituents. athom C ngoko ke inani elifunekayo umxokelelwane, ukuqala isiphelo, nto leyo substituent osondeleyo.

Okwesibini, isiseko - igama ezizizembiwa unbranched ifumile, okuhambelana inani C atom kwikhonkco ephambili.

, Ngaphambi kokusekwa kufuneka ukhankanye amagumbi Okwesithathu lokantov, ezithi zibekwe kufutshane zamasekela. Zabhalelwa kutshintsha igama hyphenated.

Okwesine, xa kwimeko substituents twatse kwi atom ezahlukeneyo C lokanty kunye, apho phambi igama livela iphindaphindeka isimaphambili: di - substituents ezimbini ezintathu - ezintathu, tetra - ezine, penta - ezintlanu, njl baNtu .. kufuneka ezahlulwe sisithuba ikoma, kwaye ukusuka amagama - iqhagamshela.

Ukuba elinye kunye C atom efanayo eziqulethwe substituents nje ezimbini lokant abhalwe kabini.

Ngokutsho le migaqo, baza bakha nokuhlelwa ngezizwe alkanes.

kwelivi Newman kaThixo

Le nososayensi eziphakanyiswayo conformations umboniso graphic nayiphi ezizodwa ifomula - nokunyuka Newman. Ziyangqinelana iifom A and B no-C ziboniswe kulo mzobo ungezantsi.

Kwimeko yokuqala Ukumila A-yathatha, ngoxa yesibini - B-elinganeno. Kwindawo A H athom zisendaweni kumgama omncinane enye kwenye. Le fom kulingana ngexabiso likhulu amandla ngenxa yokuba isizathu mkhulu therebetween. Le meko bazisa ntle, apho molecule lidla ukuba ashiye kuyo, uze uye kwindawo B. ozinzileyo ngakumbi Apha H atom somgama ubuninzi enye kwenye. Ngoko, umahluko amandla la malungiselelo - 12 kJ / Mol, ukuze ujikelezo simahla malunga ezimanyeneyo-methane molecule, edityaniswe amaqela imethyl wafumana kolwabelo olungalinganiyo. Kanye kule ndawo ngenkuthalo evumayo kwemolekyuli kukho ilibele, ngamanye amazwi, i "waqhekeza". Yiloo nto ibizwa ngokuba yi luzalwe. Isiphumo -. 10 amawaka iimolekyuli-methane sele ngohlobo Ukumila olunikiweyo lobushushu igumbi ukuncokola. omnye kuphela ngokumila eyahlukileyo - ngaphezu.

Ukulungiswa hydrocarbon Igcwele

Ukusuka inqaku kwafunyaniswa ukuba oku alkanes (isakhiwo, nokuhlelwa kubo ichazwe ngokwenkcukacha ngaphambili). Bekuya kuba akufuneki ukuba bahlolisise iindlela zabo zamalungiselelo. Bona atsalwa kwimithombo zendalo ezifana ioli, igesi yendalo, igesi ezinxulumene, namalahle. Kwakhona isicelo iindlela zokwenziwa. Umzekelo, H₂ 2H₂:

1. Inkqubo hydrogenation of hydrocarbon ezihluthiyo: CnH₂n (alkenes) → CnH₂n + 2 (alkanes) ← CnH₂n-2 (alkynes).
2. Monoxide kumxube C no H - syngas: zoth + (2n + 1) H₂ → CnH₂n + 2 + nH₂O.
3. Ukususela asidi carboxylic (iityuwa yayo): electrolysis kwi anode ukuya cathode:

• Kolbe electrolysis: 2RCOONa + 2H₂O → R-R + 2CO₂ + H₂ + 2NaOH;
• Dumas reaction (ingxubevange ngealkali): CH₃COONa + NaOH (t) → CH₄ + Na₂CO₃.

1. Ngokuhlaziya yamafutha: CnH₂n + 2 (450-700 °) → CmH₂m + 2 + cn-mH₂ (NM).
2. Gasification amafutha (okuqinileyo): C + 2H₂ → CH₄.
3. Yindibanisela alkanes leqela (halogenated) apho kukho inani amancinane athom C: 2CH₃Cl (chloromethane) + 2Na → CH₃- CH₃ (methane) + 2NaCl.
4. methanide Ukwandiswa kwamanzi (carbides metal): Al₄C₃ + 12H₂O → 4Al (OH₃) ↓ + 3CH₄ ↑.

Iimpawu ezibonakalayo of hydrocarbon Igcwele

Ukunenzela lula, idatha zihlelwe kule theyibhile.

isiphelo

Eli nqaku ingqalelo into efana alkanes (isakhiwo, nokuhlelwa, isomerism, series homologous njalo njalo.). Isixelela kancinci malunga iimpawu iphiramidi ebonisa unxibelelwano kunye kufakwe nomenclatures. Iindlela zichazwe ukuze bafumane alkanes.

Ukongeza, eli nqaku ezidweliswe ngokweenkcukacha zonke nokuhlelwa of alkanes (ukuzivavanya okunokusinceda budibane ulwazi).