Chemical Properties na alcohols

Hydrocarbon Kalam tare da daya ko fiye hydrogen atoms a cikin DNA, sauya a kan -OH kungiyar (da hydroxyl kungiyar ko hydroxy kungiyar), - shi alcohols. A sunadarai Properties ƙaddara da wani hydrocarbon m da wani hydroxyl kungiyar. Alcohols samar da raba homologue jerin cikinta wakilin kowane m bambanta daga gabanin memba ga homology bambanci m = CH2. Duk abubuwa daga wannan aji za a iya wakilta da dabara: R-OH. Domin mahadi monohydric iyakance janar sinadaran dabara ne CnH2n + 1OH. A cewar duniya nomenclature sunayen za a iya kafa ta ƙara wani hydrocarbon ƙulli ol (methanol, ethanol, propanol, da dai sauransu).

Wannan ne mai matukar bambancin da fadi da aji na sinadaran mahadi. Dangane da yawan -OH kungiyoyin a cikin DNA, shi ne zuwa kashi mono-, di- da trihydric haka a - polyhydric fili. Chemical kaddarorin da alcohols ma ya dogara ne a kan abun ciki na hydroxyl kungiyoyin kungiyoyin da kwayoyin. Wadannan kayan su ne tsaka tsaki, kuma ba dissociate cikin ions a ruwa, kamar karfi acid ko karfi sansanonin. Duk da haka, akwai iya zama a matsayin weakly acidic (rage tare da karuwa a yawan barasa kwayoyin nauyi da kuma sashe na hydrocarbon sarkar) ko asali (da karuwa tare da kara kwayoyin nauyi da kuma sashe kwayoyin) Properties.

Chemical Properties alcohols dogara ne a kan irin da na sarari tsari na atoms: ne kwayoyin da isomerism sarkar da kuma matsayin da isomers. Dangane da matsakaicin yawan guda shaidu na carbon zarra (hydroxy kungiyar daure su) da sauran carbon atoms (tare da 1 st, 2 ko 3) rarrabe farko (na al'ada), na biyu ko manyan alcohols. Primary alcohols da hydroxyl kungiyar a haɗe zuwa firamare carbon zarra. A sakandare da kuma manyan - da sakandare da kuma manyan, bi da bi. Tun propanol bayyana isomers cewa bambanta a matsayi na hydroxyl rukuni: propyl barasa C3H7-OH, kuma isopropyl barasa CH3- (CHOH) -CH3.

Wajibi ne don suna 'yan daga cikin manyan halayen da faye hali da sinadaran Properties na alcohols:

1. Lokacin da hulda da Alkali karafa ko hydroxides (deprotonation dauki) kafa alcoholates (hydrogen zarra aka maye gurbinsu da karfe zarra), dangane da hydrocarbon m samu ta hanyar methoxide, ethoxide, propoxide da sauransu, misali, sodium propylate: 2CH3CH2OH + 2Na → 2CH3CH2ONa + H2 ↑.
2. Lokacin da hulda tare da mayar da hankali hydrohalic acid kafa halogenated hydrocarbons: HBr + CH3CH2OH ↔ CH3CH2Br + H2O. Wannan dauki reversible. A sakamakon haka ne nucleophilic canza wani halogen ion, a hydroxyl kungiyar.
3. Alcohols za a iya oxidized zuwa carbon dioxide, to aldehydes ko ketones zuwa. Alcohols ƙone a gaban oxygen: 3O2 + C2H5OH → 2CO2 + 3H2O. Ƙarƙashin rinjayar da wani karfi oxidizing wakili (chromic acid, potassium permanganate , da dai sauransu) primary alcohols ana tuba zuwa aldehydes: C2H5OH → CH3COH + H2O, da kuma na biyu - to ketones: CH3- (CHOH) -CH3 → CH3- (Cho) -CH3 + H2O.
4. Dehydration dauki fitowa kan dumama a gaban dehydrating jamiái (tutiya chloride, sulfuric acid, da dai sauransu). Wannan samar alkenes: C2H5OH → CH2 = CH2 + H2O.
5. A esterification dauki ma fitowa kan dumama a gaban dehydrating mahadi, amma, da bambanci ga baya dauki a ƙananan zafin jiki da kuma samar da ethers: 2C2H5OH → -C2H5O C2H5O. Tare da sulfuric acid, da dauki auku a matakai biyu. Da farko, sulfuric acid ester aka kafa: C2H5OH + H2SO4 → C2H5O-SO2OH + H2O, bi da dumama zuwa 140 ° C da kuma wani wuce haddi na barasa da aka kafa, diethyl (sau da yawa ake magana a kai a matsayin sulfur) ether: C2H5OH + C2H5O-SO2OH → C2H5O-C2H5O + H2SO4 .

A sunadarai Properties na polyols, da misalin da su jiki Properties dogara ne a kan irin hydrocarbon m, kafa kwayoyin, kuma ba shakka, yawan hydroxyl kungiyoyin cikinta. Alal misali, ethylene glycol CH3OH-CH3OH (tafasar batu 197 ° C), wanda shi ne 2 atomic barasa ne a colorless ruwa (a zaki da dandano), wanda aka haxa shi da H2O, da kuma ƙananan alcohols a duk rabbai. Ethylene glycol a matsayin mafi girma homologues daga gare zo a cikin duk halayen halayyar monohydric alcohols. Glycerol CH2OH-CHOH-CH2OH (tafasar batu 290 ° C) ne mafi sauki wakilin 3 atomic alcohols. Shi ne wani lokacin farin ciki dadi-dandanawa ruwa, wanda shi ne mutum fiye da ruwa, amma da ya garwaya da shi a cikin wani rabo. Narkewa a cikin barasa. Domin glycerin kuma ta homologues ma halin da duk dauki na monohydric alcohols.

Chemical Properties alcohols ayyana kwatance na aikace-aikace. Suna amfani da man fetur (ethanol ko butanol, da dai sauransu), kamar yadda mai kaushi a da dama masana'antu. kamar yadda albarkatun kasa domin samar da surfactants da ƙuna. ga kira na polymeric kayan. Wasu wakilan wannan aji na gudanar da mahadi yadu amfani da lubricants ko na'ura mai aiki da karfin ruwa ruwaye, da kuma ma ga yi na medicaments da kuma ilimin aiki abubuwa.