Da samun alkenes

Alkenes - shi ne unsaturated acyclic hydrocarbons, da suka hada da daya kawai biyu bond carbon atoms. Sun samar da guda homology hadaddun (yawan) cewa ya nuna da lissafi fili na dabara CnH2n. Alal misali, da dabara a wannan na farko jerin abubuwa - ethylene - C2H4, dabara a cikin na biyar jere pentene - C5H10, goma decene - C10H20.

A carbon atoms a cikin wadannan abubuwa, a gaban wata biyu bond a Jihar hybridization sp², ta haka ne, da valence kwana daga cikin kwayoyin tsarin ne 120 °. A sauki alkene ne ethylene abu da dabara C2H4. Homologue jerin alkenes da kuma yin tunãni su sunayen, wanda ake kafa ta Bugu da kari na m prefix.

Ya kamata a lura da cewa shiri na alkenes aka ƙaddara, gabã ɗaya, ta sinadaran Properties kuma halaye. Alal misali, wadanda wanda da fiye da biyu carbon atoms kunsawa haifar isomers. Kamar wancan akwai wani abin kwaikwaya kunsha a gaskiyar cewa ya fi girma da yawan carbon atoms kunshe ne a cikin wani takamaiman alkene, da karin da ya iya samar isomers.

Jiki Properties na wadannan mahadi ma ya dogara da wuri a cikin homologue jerin. Alal misali, dab batu, ruwan aya da yawa domin ethylene ake bi da bi -169,1, -103,7 da 0,5700. A wannan sigogi na takwas a cikin jerin alkene - octene - ne daidai, bi da bi, -101,7, -121,3 da 0,7140.

Farko da samun alkenes ya faru a 1669 a lokacin da wani Jamus sunadarai Beker ware shi daga ta da tasiri na sulfuric acid a kan barasa. A wannan lokaci da masanin kimiyyar bai nuna lokacin gas jefarwa, sabili da haka ba su ba shi wani sunan, da kuma ake kira kawai "iska." Daga baya, "iska Beker" a daidai wannan hanya, da kuma samu cikin Dutch Deyman Potts Van Troostvik a 1795. Wannan lokaci, masana kimiyya sun aka bayyana a cikin daki-daki, su hanyoyin da shiri na alkenes, kuma ba su da wani suna na musamman - "maslorodny gas." Wannan sunan da aka haife shi, domin, a lokacin da dauki tare da chlorine ta samar da wani m ruwa, kawai daga baya gano a matsayin dichloroethane sunadarai daga Faransa Antuanom Furkrua.

Bugu da ƙari kuma, a cikin farkon karni na karshe da J. Gay-Lussac gano cewa ethanol hada da, ban da ainihin "maslorodnogo" gas da kuma ruwa kwayoyin.

J. Dumas da kuma P. Bull a 1928 bude samu alkenes daga ethyl chloride. Yana da ban sha'awa cewa ga mai dogon lokaci, chemists iya ba yadda ya kamata a rubuta da dabara na fili. Kawai a 1848 mowing jagorancin ethylene da kuma rubuta kamar yadda wani S4N4.

A yanayi, akwai kusan babu alkenes. Ethylene ne mafi sauki wakilin homologue jerin, shi ne a cikin nau'i na hormone a wasu shuke-shuke.

Lower alkenes ne mai guba, kuma za a iya a high yawa haifar da wani narcotic sakamako. A hali na ingestion na mafi girma alkenes za a iya lura convulsions da airway edema.

The girma na cikin kwayoyin nauyi kayyade tafasar batu da kuma narkewa wadannan mahadi da su Jihar tari. Alkenes daga farko zuwa na hudu a cikin jerin - gas daga na biyar zuwa na goma sha bakwai dauki wani nau'i na ruwa, da na gaba - daskararru. Ba tare da togiya, duk alkenes ba narkewa a cikin ruwa amma da narkewa a cikin kwayoyin kaushi.

A karkashin halin yanzu yanayi, akwai mutane da yawa hanyoyi daban-daban, don samar da alkenes. Saboda haka, to hanyoyin domin samar da alkenes, hada da wadannan masana'antu ayyuka.

Ainihin hanyar ne high zazzabi catalytic fatattaka tsari wanda ya shafi iskar gas da kuma hydrocarbon mahadi kunshe ne a cikin danyen mai. A dangane da ƙananan, yana yiwuwa su yi amfani da hanyar da ta dehydration na alcohols.

A dakunan gwaje-gwaje kuma amfani da wannan hanya, amma a nan da dauki da aka gudanar a gaban karfi acid ana kuma amfani da hanyoyin da rairaya Hoffmann da kuma Chugaeva. Ga wasu hanyoyin da rairaya dauki hada Burda, wanda shi ne kawar da bromine.

Alkenes ne ba makawa albarkatun kasa domin sinadaran masana'antu, wanda ake amfani da su samar da sararin yawa na sinadaran mahadi. Saboda haka samun alkenes ne mai muhimmanci shugabanci na ci gaban da sinadaran promyschlennosti a duk arzikin masana'antu kasashen.