Iipropati Physical of aldehydes

Ngu aldehydes ziquka iikhompawundi organic, obubonakala ngokuba yi umanyano kabini phakathi carbon neoksijini athom kunye imixokelelwane ezimbini olunye carbon atom efanayo kunye ezinkulu hydrocarbon zibonakaliswe yileta R, kunye atom hydrogen. Group of athom> C = O kuthiwa iqela carbonyl le, loo nto luphawu zonke aldehydes. aldehydes abaninzi livumba elithozamisayo. Basenokuba olulungiswe alkoholi ngu dehydrogenation (ukususwa hydrogen), yaye ngaloo ndlela wafumana igama eliqhelekileyo - aldehydes. Iipropati zimiselwa bubukho qela aldehyde carbonyl, indawo yayo molecule, kwakunye ubude lwendawo kunye eyayizalwa ye-hydrocarbon olukhulu. Oko kukuthi, ukwazi igama iziyobisi, ebonisa yayo indlela kwesakhiwo, ungalindela imichiza ethile kunye neempawu ebonakalayo aldehydes.

Kukho iindlela ezimbini eziphambili yokuthiya aldehydes. Indlela yokuqala isekelwe kwinkqubo esetyenziswa yi-International Telecommunication Union (IUPAC), oko kudla ngokuba nokuhlelwa ngendlela. Oku kusekelwe into yokuba ikhonkco mde apho atom carbon eqhotyoshelwe iqela carbonyl le, isisiseko isihloko aldehyde, oko kukuthi, igama layo livela igama alkane ezinxulumeneyo endaweni isimamva nesimamva iphindwe kwi -Al (methane - matanal, methane - ethanal propane - propanal, butane - butanal kwaye njalo njalo). Enye indlela isebenzisa ukuyilwa igama aldehydes isihloko ehambelana carboxylic acid nto leyo isiphumo igcwala (methanal - formic aldehyde, ethanal - aldehyde acetic, propanal - aldehyde na propionaldehyde, butanal - ioli aldehyde kwaye njalo njalo).

Umahluko omkhulu zokusebenza phakathi alkanes kunye aldehydes, aldehydes kujongwa iimpawu ezibonakalayo, kuba phambi kwi yokugqibela kweqela carbonyl i (> C = O). Eli qela linoxanduva umahluko iipropati emzimbeni imichiza nezinto kunye nenani elifanayo athom carbon okanye ubunzima efanayo eziphilayo. Ezi Umahluko ngenxa nokwehlukana kumaqela carbonyl> = + Sδ Oδ-. Oko kukuthi, loxinano electron kwi-atom carbon yasiwa ngayo oksijini atom, okwenza ioksijini kwenxenye electronegative kwaye electropositive carbon inxenye. Ukuze ubonise ezichaseneyo yeqela carbonyl le idla ngokusetyenziswa ileta Delta lesiGrike (δ), oku kubonisa ityala buso. Isiphelo esibi omnye molecule polar uthanda ekupheleni ezintle komnye molecule polar. Le molecule zinokufana nokuba nezinye impahla. Aldehydes, ketones yahlukile kule carbon yokugqibela qela carbonyl i elidityaniswe ngeentambo enye radicals ezimbini hydrocarbon. Kule meko ke umdla kwakhona ukuthelekisa iimpawu ezibonakalayo ze aldehydes kunye ketones.

It iqela wokwephuka> C = O kuchaphazela iimpawu ezibonakalayo le aldehyde: lobushushu iqondo lokubila le lokubila, ukunyibilika, dipole mzuzu. iikhompawundi hydrocarbon ezinamaphepha kuphela yeehidrojeni nembumba yeekharbon athom, anyibilike uphekele kumaqondo obushushu aphantsi. Xa izinto kunye neqela carbonyl i ezi aphezulu kakhulu. Umzekelo, butane (CH3CH2CH2CH3), propanal (CH3CH2CHO) kunye acetone (CH3SOSN3) ezinobunzima olufanayo beemolekyuli ka 58 kwaye indawo abilileyo butane ngu-0 ° C, lo gama kuba propanal ngayo yi-49 ° C, kanti acetone yi 56 ° C. Isizathu sokuba umahluko omkhulu kakhulu ngenxa yokuba molekyuli polar babe nethuba ngakumbi ukuba ninomdla omnye ngaphandle molekyuli non-polar, ngoko ngokwaphulwa yabo ifuna amandla ngakumbi yaye, ke ngoko, ifuna ubushushu bayinyibilikisa compound okanye ebilisiweyo.

Ngenxa yokwanda ubunzima ngemolekyula ngenxa yokutshintsha iimpawu ebonakalayo aldehydes. Formaldehyde (HCHO) lulwelo sukube kwi kwiimeko eziqhelekileyo, acetaldehyde (CH3CHO) amathumba kwiqondo lobushushu igumbi. Ezinye aldehydes (ngaphandle kwabo ukusuka ubunzima eliphezulu molecule) phantsi kweemeko yemigangatho ulwelo. molekyuli Polar musa ukudibanisa lula ne non-polar kuba molekyuli polar ninomdla omnye komnye, i-non-polar kwaye akanako ukungena phakathi kwabo. Ngoko ke hydrocarbon azikho enyibilikayo emanzini, ekubeni iimolekyuli yamanzi ezibandayo. Aldehydes iimolekyuli apho inani athom carbon lingaphantsi kwe-5, iqhawulwa ngamanzi, kodwa ukuba inani athom carbon mkhulu ku-5, kuphela kwenzeka. aldehydes ukunyibilika Good ukusuka ubunzima molekyuli ephantsi ngenxa ukuyilwa imixokelelwane hydrogen phakathi hydrogen atom kwemolekyuli yamanzi neoksijini atom iqela carbonyl le.

Ezichaseneyo le molekyuli lisekwa atom ezahlukeneyo, kungenziwa nangokobungakanani oluvakaliswe linani, ekuthiwa mzuzu dipole. Molecule akhiwa atom ezifanayo akukho polar kwaye akukho mzuzu dipole. mzuzu Vector dipole ijoliswe kwabo isiqalelo emi lwezakhi (ukuba kwithuba elinye) ukuya ngasekunene. Ukuba molecule ubunjwe atom iqelana mnye, loxinano electron uya shift ekuyeni element kunye nenombolo nolandelelwano elincinci. Inkoliso hydrocarbon akukho mzuzu dipole okanye ubukhulu yayo incinane kakhulu, kodwa ke aldehydes eziphezulu kakhulu, nto leyo echaza iimpawu ebonakalayo aldehydes.