International nomenclature na alkanes. Alkanes: tsarin, Properties

Yana da amfani fara da maanar alkanes. Wannan da cikakken ko cikakken hydrocarbons, paraffins. Mun kuma iya cewa shi carbons a wadda fili C kwayoyin halitta aka yi ta hanyar sauki a tsakaninsu. A general dabara ne na form: CnH₂n + 2.

An sani cewa da rabo daga H da kuma C kwayoyin halitta a cikin kwayoyin kamar yadda zai yiwu a lokacin da idan aka kwatanta da sauran azuzuwan. Ganin cewa duk valences suna shagaltar ko C, ko H, da kuma sinadaran Properties na alkanes bayyana haske isa, don haka su biyu suna protrudes jumlar iyaka ko cikakken hydrocarbons.

akwai kuma wani karin tsoho sunan cewa mafi kyau nuna su zumunta himinertnost - paraffins, wanda fassara nufin "rasa dangantaka".

Saboda haka, da topic na mu na yau tattaunawar: "Alka: homologue jerin, nomenclature, tsari da isomerism". So kuma ba data da su game da jiki Properties.

Alkanes: tsarin, nomenclature

A cikin wadannan C kwayoyin halitta ne a cikin irin wannan jiha kamar sp3-hybridization. Saboda haka alkane kwayoyin za a iya nuna a matsayin sa na tetrahedral Tsarin C, wanda suna da alaka ba kawai a tsakãninsu amma kuma tare da H.

Tsakanin C da H kwayoyin halitta ne ba m, sosai low iyakacin duniya s-bond. Kwayoyin halitta a kusa da guda shaidu ko da yaushe juya a matsayin sakamako na alkanes kwayoyin dauki daban-daban siffofin, cikinsa da tsawon na connection, da kwana tsakanin su - suna constants. Forms, wanda ya canza kama zuwa juna saboda juyawa daga cikin DNA, wanda ya auku a kusa da σ-shaidu, kira a matsayin ta conformation.

A kan aiwatar da detachment daga H sunadaran kwayoyin Forms 1-valent barbashi kira hydrocarbon radicals. Wadannan mahadi sakamakon ba kawai gudanar da mahadi amma kuma inorganic. Idan muka ɗebe biyu hydrogen zarra daga hydrocarbon kwayoyin iyaka, daya obtains 2-valence radicals.

Kamar wancan alkanes iya zama nomenclature:

• radial (tsohon version).
• Canzawa (kasa da kasa,-din-din). Ta samarwa da IUPAC.

Musamman radial nomenclature

A cikin farko idan nomenclature alkanes halin kamar haka:

1. Shawara hydrocarbons kamar yadda Kalam na methane, wanda aka maye by 1 ko fiye H kwayoyin halitta radicals.
2. A babban mataki na saukaka a cikin hali na ba sosai hadaddun mahadi.

Features na sauyawa nomenclature

Canzawa nomenclature alkane yana da wadannan siffofin:

1. Dalili na sunan - 1 da carbon sarkar, da kuma sauran kwayoyin da wani ɓaɓɓake ake gani a matsayin substituents.
2. Idan akwai mahara m radicals kafin su sunan nuna lamba (tsananin a kalmomi), da kuma m lambobin rabu da wakafi.

Chemistry: nomenclature na alkanes

Domin saukaka, bayanai da aka gabatar a tabular form.

The sama nomenclature alkanes hada sunayen tarihi suna kafa (na farko 4 sharuddan daga cikin jerin cikakken hydrocarbons).

Ga nondeployed alkanes tare 5 ko fiye C kafa daga Greek numerals kwayoyin halitta wadda gani a ba yawan sunadaran C. Kamar wancan -en kari na baya baki ya nuna cewa abu da dama da cikakken mahadi.

A jawo lakabi tura alkanes matsayin babban sarkar da aka zaba a cikin daya da cewa ya ƙunshi matsakaicin yawan sunadaran C. Yana da aka ƙidaya haka cewa substituents da karami lambar. A cikin yanayin biyu ko fiye da sarƙoƙi na daidaita tsawon zama da babban daya wanda yana dauke da mafi yawan substituents.

isomerism na alkanes

Kamar yadda hydrocarbon-kafa a yawan ayyukan methane CH₄. Tare da kowane wakilin methane jerin lura a bambanta da na baya methylene kungiyar - CH₂. Wannan abin kwaikwaya za a iya gano a ko'ina cikin jerin alkanes.

Bajamushe masanin kimiyya Schill sa a gaba wani tsari don suna da yawan homologue. Fassara daga Girkanci ma'anar "kama, kamar."

Saboda haka, homologue jerin - a sa na related gudanar da mahadi da ciwon guda irin tsarin da kusa himsvoystvami. Homologs - da mambobi daga cikin jerin. Homologue bambancin - methylene kungiyar ta wadda biyu daban-daban m homologue.

Kamar yadda aka ambata a baya, wani abun da ke ciki na da cikakken hydrocarbon iya bayyana ta da janar dabara CnH₂n + 2. Saboda haka, wadannan da methane ne memba na homologue jerin ethane - C₂H₆. Don kacokan tsarin methane, shi wajibi ne don maye gurbin H zarra a cikin 1 CH₃ (adadi a kasa).

A tsarin kowace m homologue za a iya samu daga sama a cikin wannan hanya. A sakamakon ethane kafa propane - C₃H₈.

Menene isomers?

Shin abubuwa da cewa suna da wani m ingantaccen da kuma gwada yawa kwayoyin abun da ke ciki (m kwayoyin dabara) amma daban-daban sinadaran Tsarin da ciwon daban-daban himsvoystvami.

Halin da waccan mujalla da muka hydrocarbons a kan irin wannan siga a matsayin tafasar zazzabi: -0,5 ° - butane, -10 ° - isobutane. Wannan irin isomerism ake magana a kai a matsayin carbonaceous kwarangwal isomerism, shi da dangantaka da tsarin irin.

Yawan tsarin isomers qara hanzari tare da yawan carbon atoms. Saboda haka, C₁₀H₂₂ zai dace isomers 75 (ba ciki har da sarari), kuma domin 4347 C₁₅H₃₂ riga aka sani isomers, domin C₂₀H₄₂ - 366.319.

Saboda haka riga ya bayyana cewa irin wannan alkanes, homologue jerin, isomerism, nomenclature. Yanzu ya zama dole don su tafi da dokoki domin IUPAC sunayen.

IUPAC nomenclature: Sunan ilimi

Da fari dai, wajibi ne a sami wani tsarin da wani hydrocarbon carbon sarkar, wanda ya ƙunshi mafi tsawon kuma matsakaicin yawan substituents. Sa'an nan da ake bukata da dama da sarkar C kwayoyin halitta, fara daga karshen, wanda shi ne mafi kusa substituent.

Abu na biyu, tushen - da sunan unbranched cikakken hydrocarbon, wanda yayi dace da yawan C kwayoyin halitta ne babban sarkar.

Na uku, kafin kafuwar dole saka lokantov dakuna, wanda ake dake kusa da wakilai,. Suka rubuta hyphenated sunan jũyar.

A nan, idan akwai m substituents a kan daban-daban kwayoyin halitta C lokanty tare, a cikinta kafin sunan bayyana ninka prefix: di - biyu m substituents uku - uku, tetra - hudu, Penta - to biyar, da dai sauransu .. Figures su dole ne a raba ta a wakafi, da kuma daga cikin kalmomi - jan layi.

Idan daya da kuma guda C zarra dauke kawai biyu substituents lokant kuma rubuta sau biyu.

A cewar wadannan dokoki, da kuma kafa na duniya nomenclature na alkanes.

Newman ta tsinkaya

Wannan American masanin kimiyya shawarce hoto zanga-zanga conformations musamman tsinkaya dabara - Newman tsinkaya. Su dace da siffofin A da B da C aka nuna a cikin adadi a kasa.

A cikin farko idan na A-husufi conformation, yayin da na biyu - B-hana. A matsayin A H kwayoyin halitta suna located a mafi žarancin nisa daga juna. Wannan nau'i yayi dace da most darajar da makamashi saboda gaskiyar cewa mafi girma tunkuxe therebetween. Wannan energetically unfavorable jihar, inda da kwayoyin o ƙarin bar shi, da kuma matsawa zuwa wani more barga matsayin B. nan da H sunadaran matsakaicin nesa daga juna. Saboda haka, da samar da makamashi bambanci na wadannan kayan abinci - 12 KJ / mol, don haka da cewa free juyawa a kusa da axis na kwayoyin ethane, wanda ta haɗu da methyl kungiyoyin samu m. Da zarar a cikin energetically m matsayi na kwayoyin akwai jinkirta zuwansa, a cikin wasu kalmomi, da "birki". Wannan shi ne dalilin da ya sa shi ne ake kira retarded. Result -. 10 dubu ethane kwayoyin ne a cikin nau'i na hana conformation bayar dakin da zazzabi. Daya kawai yana da wani daban-daban siffar - husufi.

Shiri na cikakken hydrocarbons

Daga cikin labarin an koya cewa wannan alkanes (tsarin, nomenclature na su bayyana a cikin daki-daki, a baya). Yana zai zama superfluous, don su bincika su hanyoyin da shirye-shiryen. Suna cirewa daga halitta kafofin kamar mai, iskar gas, hade gas, kwal. Har ila yau tambaya roba hanyoyin. Alal misali, H₂ 2H₂:

1. A tsari na hydrogenation na unsaturated hydrocarbons: CnH₂n (alkenes) → CnH₂n + 2 (alkanes) ← CnH₂n-2 (alkynes).
2. Monoxide daga cakuda C da H - syngas: nCO + (2n + 1) H₂ → CnH₂n + 2 + nH₂O.
3. Daga carboxylic acid (salts daga gare): electrolysis a anode ga cathode:

• Kolbe electrolysis: 2RCOONa + 2H₂O → R-R + 2CO₂ + H₂ + 2NaOH.
• Dumas dauki (gami da Alkali): CH₃COONa + NaOH (t) → CH₄ + Na₂CO₃.

1. Fatattaka daga man fetur: CnH₂n + 2 (450-700 °) → CmH₂m + 2 + CN-mH₂ (nm).
2. Gasification na man fetur (m): C + 2H₂ → CH₄.
3. Kira na hadaddun alkanes (halogenated) wanda da kadan yawan sunadaran C: 2CH₃Cl (chloromethane) + 2Na → CH₃- CH₃ (ethane) + 2NaCl.
4. Fadada ruwa methanide (karfe carbides): Al₄C₃ + 12H₂O → 4Al (OH₃) ↓ + 3CH₄ ↑.

The jiki Properties na cikakken hydrocarbons

Domin saukaka, da data suna harhada a tebur.

ƙarshe

A labarin da aka dauke da irin wannan abu a matsayin alkanes (tsarin, nomenclature, isomerism, homologue jerin da sauransu.). Yana gaya mana kadan game da siffofin na radial da canzawa nomenclatures. Hanyoyin da ake da aka bayyana domin samun alkanes.

Bugu da kari, da labarin da aka jera a cikin daki-daki, duk da nomenclature na alkanes (gwajin zai iya taimaka wa assimilate da bayanai).