Unsaturated hydrocarbons: alkenes, sinadaran Properties da aikace-aikace

Alkenes - unsaturated hydrocarbons wanda kwayoyin tsakanin biyu carbon atoms, daya biyu bond. Su sukan kira hydrocarbons ethylene jerin, domin shi ne mai sauki wakilin ethylene NC2 = CH2. Wani lokaci wadannan hydrocarbons ake olefins kamar yadda gaseous alkenes maida martani tare da bromine ko chlorine ta samar da m mahadi da cewa ba su narkewa a cikin ruwa. The kalmar "alkenes" IUPAC nomenclature aka samu daga kalmar "alkanes", inda -an kari na baya baki aka maye gurbinsu da kari na baya baki -ene, wanda ya nuna gaban a cikin kwayoyin na abu na biyu bond.

Unsaturated hydrocarbons - alkenes: tsarin

All alkenes dauke Kalam na ethylene ko ethene - C2H4.

A ethylene kwayoyin ƙunshi biyu carbon kwayoyin zarra da hudu hydrogen atoms, da unsaturated carbon atoms. Kowace daga cikin unsaturated carbon zarra hybridizes es daya da biyu pi-orbitals, kuma daya pi orbital saura a "m nau'i", da samar da matsakaicin nesa na hybridized lantarki orbitals. su gatura samar 120 °. Wannan halitta mafi kyau duka yanayi na zoba na electron orbitals. Uku irin orbitals na carbon atoms ta samar da uku sigma shaidu (biyu C-H, C-C wani). Saboda haka, da ethylene kwayoyin yana da biyar sigma shaidu wanda aka sarrafa a cikin wannan jirgin sama, kafa tsakanin su wani kwana na 120 °. P-electrons da cewa kasance a cikin "tsarki" ya samar da wani bond tsakanin biyu carbon atoms. Aka bayyana lantarki tsarin ethylene kwayoyin hali na alkenes. Unsaturated hydrocarbons ne da za a daukarsa a matsayin Kalam na ethylene.

Domin alkene halin 2 iri isomerism - lissafi da kuma tsarin.

Tsarin isomers na alkenes fara da butene C4H8. Bambanta da ta bambance-bambancen karatu - sarkar isomerism (ko carbon kwarangwal) da kuma isomers jeri na biyu bond a cikin irin wannan rangadi.

Lissafi isomerism saboda m jeri na hydrogen substituents a cikin kwayoyin na ethylene dangi da jirgin sama na biyu bond. Unsaturated hydrocarbons ne cis- kuma trans-isomers.

Alkenes a free jihar ne da wuya a yanayi. Suka hada yin amfani da masana'antu da kuma awon tafiyar matakai.

Chemical Properties na hydrocarbons: alkenes

Suna sa da wani biyu bond tsakanin biyu carbon atoms a cikin kwayoyin na wani alkene.

A hydrogenation dauki

Alkenes amsa readily abin da aka makala na hydrogen. Yana auku a gaban catalysts ko da dumama:

CH2 = CH2 = H2 H3C CH3

shiga halides

A dauki Saide ta da Markovnikov mulki, Ina nufin ta maida martani a hydrogen halide da asymmetric kwayoyin alkenes hydrogen da aka kara a wuri na sarrafawa na biyu bond zai fi dacewa da carbon zarra kusa da akwai mafi hydrogen atoms, a halogen zarra - zuwa carbon zarra kusa da kasa hydrogen atoms ko gaba daya ba su zama:

CH3-CH = CH2 + HC1-CH3-CH3-CHC1.

A amfani da hydrocarbons

Ethene - gas dissolves da kyau a barasa da kuma talauci mai narkewa a cikin ruwa, fashewar.

Su ne mai arziki a cikin fatattaka gas (har zuwa 20% na jimlar nauyi) da kuma coke tanda gas (kamar 5%). A cikin dakin gwaje-gwaje da hanyoyin da dehydration ethylene shirya dehydrogenation na ethane da ethanol. Amfani da su samu ethylene ethyl barasa, vinyl chloride, ethylbenzyl, polyethylene, maganin daskarewa jamiái (abubuwa da rage da sanyinsu na ruwa a cikin injuna) da sauran kwayoyin abubuwa. A adam da dabbobi magani, ethylene aka yi amfani a matsayin magani halitta a cikin amfanin gona - a gaggauta ripening 'ya'yan itatuwa (tumatir, lemons, da kuma kamar).

Propylene an samu tare da ethylene a pyrolysis da fatattaka daga daban-daban daban na man fetur feedstock. Propylene - wani bangaren na mota man fetur. Ana amfani da matsayin feedstock for propylene, isopropylbenzyl, isopropyl barasa. Tare da isopropanol, acetone, tare da isopropylbenzyl - acetone da phenol. Propylene aka yi amfani a matsayin narcotic miyagun ƙwayoyi domin rairaya acrylonitrile, cumene, butanol, da dai sauransu