Thepa ya moaho wa aldehydes

Ke aldehydes kenyeletsa metsoako manyolo, tse tsejoang ka tlamo habeli pakeng tsa k'habone le oksijene liathomo le tse peli litlamo le 'ngoe ea tšoanang k'habone athomo ka hydrocarbon khōlō denoted ke lengolo R, le athomo hydrogen e. Sehlopha sa liathomo> C = O bitsoa carbonyl sehlopha, ho ke ke bath ea aldehydes tsohle. aldehydes bangata ba na le monko monate. Ba ka 'na ka lokisoa ho tloha alcohols ke dehydrogenation (tloswa hydrogen),' me ka tsela eo, o ile a fumana lebitso la tloaelehile hore batho ba - aldehydes. Properties ikemiselitse ke ho ba teng ha aldehyde carbonyl sehlopha, sebakeng sona ka molek'hule ea, hammoho le bolelele tlhaloganya sebaka le branching ea hydrocarbon khōlō. Ke hore, ho tseba lebitso la ntho e, ho nahana lona moralo mehaho, o ka lebella hore itseng tsa lik'hemik'hale le thepa meleng aldehydes.

Ho na le litsela tse peli tse ka sehloohong sa reha lebitso aldehydes. The mokhoa pele e thehiloe tsamaiso ea sebelisoa ke tlhaeletsanong ya Union International (IUPAC), e atisa ho bitsoa nomenclature hlophisitsoeng. E thehiloe 'nete ea hore ketane telele ka ho fetisisa eo ka eona carbon athomo khomaretse sehlopha carbonyl, bopa motheong oa sehlooho aldehyde, ke hore, lebitso la oona le tsoa lebitso la alkane amanang ka ho fetola suffix -e leng suffix ka -Al (methane e - matanal, hlahisoang moo ethane - ethanal Propane - propanal, butane - butanal joalo joalo). mokhoa o mong sebedisa sebopeho sa aldehydes sehlooho lebitso ngollana acid e carboxylic eo hape ka lebaka la ho kena moea (methanal - formic aldehyde, ethanal - acetic aldehyde, propanal - aldehyde ke propionaldehyde, butanal - oli aldehyde joalo joalo).

Ka sehloohong mehaho phapang pakeng tsa alkanes le aldehydes, aldehydes beha thepa 'meleng, ke ho ba teng ha ka bobeli ba carbonyl sehlopha (> C = O). Sehlopha sena ke le boikarabelo ba ho se tšoane ha thepa 'meleng le lik'hemik'hale tsa lintho le palo e tšoanang ea liathomo k'habone kapa e tšoanang boima ea limolek'hule. tšoane hona ke ka lebaka la karohanyo ea lihlopha carbonyl> = + Sδ Oδ-. Ke hore, segokanyipalo elektrone ka har'a carbon athomo ile a khaotsa ka nģ'a oksijene athomo, e etsa hore oksijene e leeme electronegative le electropositive k'habone karolo. Ho bontsha polarity tsa sehlopha carbonyl e atisa ho sebelisa Segerike lengolo makgobokgobo (δ), ena e bontša ka leeme qoso. Qetellong mpe tsa molek'hule e 'ngoe Polar a khahliloe ke ho fela ntle tsa molek'hule e' ngoe Polar. molek'hule ena e ka ba e tšoanang hore na ntho tse ling. Aldehydes, ketones se fapane le sa carbon ho qetela tsa sehlopha carbonyl e amana ka litlamo le le leng le radicals pedi hydrocarbon. Tabeng ena e boetse e thahasellisang ho bapisa thepa 'meleng oa aldehydes le ketones.

Ho polarity sehlopha> C = O ama thepa meleng aldehyde le: ka qhibiliha ntlha mocheso oa belisoa ntlha, solubility, moment motsotso. Hydrocarbon metsoako eo e na le feela haedrojene le k'habone liathomo, qhibiliha le lethopa ka thempereichara e tlaase. Ka thepa le sehlopha carbonyl ke haholo e phahameng. Mohlala, butane (CH3CH2CH2CH3), propanal (CH3CH2CHO) le monohalogen acetone (CH3SOSN3) na le limolek'hule boima o tšoanang oa ho 58 le belisoe ntlha ka butane ke 0 ° C, ha a ntse a bakeng sa propanal ho 49 ° C, ha a ntse monohalogen acetone ke 56 ° C. The le lebaka la ho phapang e kholo itšetlehile ka 'nete ea hore limolek'hule Polar ba le monyetla oa ho feta ho khahloa ke e mong le e tse ling tse ho feta limolek'hule bao e seng Polar hona fracture bona hloka le matla a eketsehileng le hona, le hloka mocheso ho feta ho qhibiliha le komponeng kapa phehiloeng.

Le e ntseng e eketseha boima ba 'mele ea limolek'hule tsa ho fetola thepa meleng aldehydes. Formaldehyde (HCHO) ke gaseous ntho ka maemo a tloaelehileng, acetaldehyde (CH3CHO) taba ka mocheso kamore. aldehydes tse ling (ntle le tseo ho tswa ho boima phahameng limolek'hule) tlas'a maemo a tekanyetso ke mokelikeli. limolek'hule Polar se kopanya habonolo le batho bao e seng Polar hobane limolek'hule Polar ba khahloa mong ho e mong, le batho bao e seng Polar le sa khone ho pepeta pakeng tsa bona. Ka hona hydrocarbons ha qhibilihang ka har'a ka metsi, ho tloha limolek'hule metsi ke Polar. Aldehydes limolek'hule oo palo ea liathomo k'habone tlaase ho feta 5, ba qhalwa ho ya ka metsi, empa ha lenane la liathomo k'habone le leholo ho 5, shoa hoa etsahala. Good solubility aldehydes tloha boima tlaase limolek'hule e loketseng hore ho thehoe litlamo hydrogen pakeng tsa athomo hydrogen tsa metsi molek'hule le oksijene athomo ea sehlopha carbonyl.

The polarity ea limolek'hule le thehoa ka liathomo tse sa tšoaneng, li ka quantitatively bontšoa ke palo, e bitsoang moment motsotso. Molek'hule thehoa ke liathomo tšoanang ha Polar le na motsotso moment. Vector moment motsotso laela ikutloeleng elements eme tafole nako le nako (bakeng sa nako e 'ngoe) ka ho le letona. Ha molek'hule e entsoe ka liathomo tsa lesikeng le 'ngoe, elektrone segokanyipalo tla jarisa ikutloeleng elements le palo e nyenyane a latellana joang. Boholo ba hydrocarbons ho na motsotso moment kapa boholo lona ke tse nyenyane ka ho fetisisa, empa e aldehydes e phahameng haholo, e leng e boetse e hlalosa ka thepa meleng aldehydes.