Ngā āhuatanga ōkiko o aldehydes

Na roto i te aldehydes ngā pūhui matū waro, e kua āhuatanga e te here rua i waenganui i te waro me te hāora ngota, me te kotahi here e rua o te ngota waro taua ki te tuwhena pūwaro denoted e te R pukapuka, me te ngota hauwai. i huaina Group o ngota> C = e te te rōpū carbonyl, he reira āhuatanga o te aldehydes katoa. He maha aldehydes i te kakara ahuareka. kia kia rite ratou i waiwaihā i dehydrogenation (tango hauwai), a reira riro ingoa noa - aldehydes. E whakaritea Āhuatanga i te aroaro o te rōpū hāparo-tahi carbonyl, tona wāhi i roto i te rāpoi ngota, me te te roa mokowā, me te wana o te pūwaro tuwhena. Ko, te mohio ki nga ingoa o te taonga, e whakaata ana tona tātai hanganga, ka taea e koe e mahara etahi matū me ngā āhuatanga ōkiko o aldehydes.

E rua ara matua o whakaingoa aldehydes. hāngai ana te tikanga tuatahi i runga i te pūnaha e whakamahia ana e te International Telecommunication Union (IUPAC), Kei te maha huaina reira nomenclature nahanaha. Kei te hāngai te reira i runga i te meka e te mekameka roa i roto i nei te ngota waro piri ki te rōpū carbonyl, te pūtake o te taitara hāparo-tahi, e ko, haere mai tona ingoa i te ingoa o te waiwaro tahi e hāngai ana mā te whakakapi i te pīmuri pīmuri -ko i runga i hāparo-tahi (mewaro - matanal, ewaro - hāparo- pōwaro - propanal, pūwaro - butanal me pera i runga i). whakamahi tētahi atu tikanga te hanganga o te ingoa aldehydes taitara hāngai waikawa i roto i te tahuri te hua o te piti hāora (tahi mewaro - formic hāparo-tahi, hāparo-- hāparo-tahi ahetiki, propanal - hāparo-tahi he propionaldehyde, butanal - hinu hāparo-tahi, me te pera i runga i).

Ko te rerekētanga hanganga matua i waenganui i waiwaro tahi me aldehydes, aldehydes whakatau ngā āhuatanga ōkiko, ko te aroaro i roto i te whakamutunga o te rōpū carbonyl (> C = e). Tenei rōpū te kawenga mō te rerekētanga i roto i ngā āhuatanga ā-tinana, me te matū o matū ki te taua maha o ngā ngota waro te taimaha rāpoi taua ranei. E tika ana ki te vahiraa o te rōpū carbonyl> = + Sδ Oδ- enei rerekētanga. Ko, te kiato irahiko i runga i te ngota waro neke ki te hāora ngota, hanga i te hāora wāhanga waro electronegative me electropositive wahi. Hei tohu te maha whakamahia te wehenga tawhiti o te rōpū carbonyl raorao reta Kariki (δ), tohu tenei he tiaki te kanohi. ngā te mutunga kino o tetahi muingota neke te ki te pito pai o tetahi rāpoi ngota neke. pea te taua ranei te tahi atu taonga tenei rāpoi ngota. Aldehydes, ketones rerekē i taua i roto i te waro whakamutunga o te rōpū carbonyl hono e kotahi here ki Radicals waiwaro rua. I roto i tenei horopaki ko reira ngā ano hoki ki te whakarite i te āhuatanga ōkiko o aldehydes me ketones.

Te reira i te rōpū wehenga tawhiti> C = e pānga nga āhuatanga ōkiko o te hāparo-tahi: he pāmahana ira whakakoero o te wāhi e koropupu, memehatanga, dipole kau. pūhui pūwaro e roto i hauwai me te waro anake ngota, ngohe me te whewhe i pāmahana iti. I roto i ngā rauemi ki te rōpū carbonyl e tino teitei. Hei tauira, pūwaro (CH3CH2CH2CH3), propanal (CH3CH2CHO) me hauwaiwaro (CH3SOSN3) i te papatipu rāpoi taua o 58 me te ira koropupū i roto i te pūwaro ko 0 ° C, i hoki propanal ko reira 49 ° C, i te hauwaiwaro ko 56 ° C. Ko te take mo te rerekētanga nui takoto i roto i te meka e rāpoi neke whai atu rave'a ki te kia ngā ki ia atu atu i te rāpoi kore-neke, koia ratou whati rapu atu pūngao me, reira, titau wera atu ki te ngohe i te pūhui kohuatia ranei.

Ki te whakanui ake i te taimaha o rāpoi te huri nga āhuatanga ōkiko o aldehydes. Formaldehyde (HCHO) ko te taonga haurehu waihā i tikanga noa, acetaldehyde (CH3CHO) whewhe i te pāmahana rūma. He wai Ētahi aldehydes (anake te hunga i te taimaha rāpoi teitei) i raro i ngā āhuatanga paerewa. e kore e rāpoi neke uru ngāwari ki kore-neke no te mea kei te ngā i te rāpoi neke ki tetahi ki tetahi, te kore-neke, me te e kore e taea e ki te kotēhia i waenganui ia ratou. Na reira e kore e wairewa i roto i te wai i te waiwaro, mai he neke nga rāpoi ngota wai. i roto i i rewa rāpoi ngota Aldehydes te maha o ngā ngota waro i raro i te 5, e i roto i te wai, engari ki te te maha o ngā ngota waro nui ake i te 5, puta whakakorenga. aldehydes memehatanga pai i iti te taimaha rāpoi tika ki te hanganga o here hauwai i waenganui i te ngota hauwai o te muingota wai me te hāora ngota o te rōpū carbonyl.

Ko te wehenga tawhiti o te rāpoi ngota i hanga e te ngota rerekē, ka taea te ine nui whakahuatia e te maha, ka karanga dipole kau. Rāpoi ngota i hanga e te taua ngota e kore e neke, me te whai kore dipole kau. whakahaua Vector dipole kau ki te huānga e tu ana i roto i te ripanga pūmotu (mō te kotahi wā) ki te tika. Ki te titoa te muingota te o ngota o tetahi Huingaiti, ka nuku i te kiato irahiko ki te huānga ki te tau raupapa iti. Te nuinga o nga waiwaro he kahore momeniti dipole ranei he tino iti tona nui, engari he reira aldehydes nui teitei, ano e whakamārama te āhuatanga ōkiko o aldehydes.