Jiki Properties na aldehydes

Aldehydes ne gudanar da mahadi, wanda aka halin da biyu bond tsakanin carbon da oxygen kwayoyin zarra da biyu guda shaidu na wannan carbon zarra na wani hydrocarbon m, denoted da wasika R, da kuma wani hydrogen zarra. Group of kwayoyin halitta> C = Yã ake kira da carbonyl kungiyar, shi ne halayyar duk aldehydes. Mutane da yawa aldehydes da m wari. Sun iya shirya daga alcohols da dehydrogenation (hydrogen kau), kuma da ita sami kowa sunan - aldehydes. Properties aka ƙaddara ta a gaban aldehyde carbonyl kungiyar, ta wuri a cikin DNA, kazalika da na sarari tsawon da sashe na hydrocarbon m. Wannan shi ne, sanin sunan abu, nuna ta tsarin dabara, za ka iya sa ran wasu sinadaran da jiki Properties na aldehydes.

Akwai manyan hanyoyi biyu na ambata sunayen aldehydes. A farko hanyar dogara ne a kan tsarin amfani da kasa da kasa Sadarwa Union (IUPAC), shi ne sau da yawa kira din nomenclature. Ya dogara ne a kan gaskiyar cewa mafi tsawo sarkar a cikin abin da carbon zarra a haɗe zuwa carbonyl kungiyar, Forms tushen da aldehyde take, cewa shi ne, da sunan da ya zo daga sunan related alkane ta maye gurbin da kari na baya baki -an kari na baya baki a kan -Al (methane - matanal, ethane - ethanal propane - propanal, butane - butanal da sauransu). Wani Hanyar yana amfani da samuwar aldehydes suna sunan m carboxylic acid wanda bi da bi da sakamakon hadawan abu da iskar shaka (methanal - formic aldehyde, ethanal - acetic aldehyde, propanal - aldehyde ne propionaldehyde, butanal - aldehyde mai da sauransu).

Babban tsarin bambanci tsakanin alkanes da aldehydes, da kayyade jiki Properties na aldehydes, shi ne kasancewar a karshen na carbonyl kungiyar (> C = Yã). Wannan kungiyar ce ke da alhakin bambance-bambance a jiki da kuma sinadaran Properties na abubuwa da wannan adadin carbon atoms ko guda kwayoyin nauyi. Wadannan bambance-bambance ne saboda da rabuwa da carbonyl kungiyoyin> = + Sδ Oδ-. Wato, da electron yawa a kan carbon zarra canja zuwa ga oxygen zarra, yin oxygen m electronegative da electropositive carbon part. Don nuna polarity na carbonyl kungiyar ne sau da yawa amfani Greek harafi Delta (δ), wannan ya nuna wani m cajin. A korau karshen daya iyakacin duniya kwayoyin da aka janyo hankalin zuwa tabbatacce karshen wani iyakacin duniya kwayoyin. Wannan kwayoyin iya zama guda ko wasu abu. Aldehydes, ketones daban-daban daga cewa a karshe carbon na carbonyl kungiyar an haɗa da guda shaidu da biyu hydrocarbon radicals. A wannan mahallin shi ne ma ban sha'awa kwatanta jiki Properties na aldehydes da ketones.

Yana polarity kungiyar> C = Ya rinjayar da jiki Properties na aldehyde: wani narkewa batu zafin jiki na tafasar batu, solubility, dipole lokacin. Hydrocarbon mahadi da cewa dauke da kawai hydrogen da carbon atoms, narke da kuma tafasa a low yanayin zafi. A kayan da carbonyl kungiyar ne muhimmanci mafi girma. Alal misali, butane (CH3CH2CH2CH3), propanal (CH3CH2CHO) da kuma acetone (CH3SOSN3) da wannan kwayoyin nauyi na 58 da kuma wani tafasar batu a butane ne 0 ° C, yayin for propanal shi ne 49 ° C, yayin da acetone ne 56 ° C. Dalilin da babban bambanci ta'allaka ne da cewa iyakacin duniya kwayoyin da karin damar da za a janyo hankalin juna fiye da wadanda ba na iyakacin duniya kwayoyin, don haka dole ne su zama more makamashi rata da haka na bukatar a babbar zazzabi ya narke da mahadi, ko Boiled.

Tare da kara kwayoyin nauyi na canza jiki Properties na aldehydes. Formaldehyde (HCHO) ne a gaseous abu a al'ada yanayi, acetaldehyde (CH3CHO) tafasa a dakin da zazzabi. Sauran aldehydes (fãce waɗanda daga high kwayoyin nauyi) a karkashin tuta yanayi ne ruwa. Iyakacin duniya kwayoyin ba su gauraya sauƙi tare da wadanda ba na iyakacin duniya saboda iyakacin duniya kwayoyin suna janyo hankalin zuwa juna, da ba iyakacin duniya da kuma ba su iya matsi tsakanin su. Saboda haka hydrocarbons ba narkewa a cikin ruwa, tun da ruwa kwayoyin ne iyakacin duniya. Aldehydes kwayoyin a cikin abin da yawan carbon atoms ƙananan fiye da 5, an narkar da a ruwa, amma idan yawan carbon atoms fi 5, rushe faruwa. Good solubility aldehydes daga low kwayoyin nauyi saboda da samuwar hydrogen shaidu tsakanin hydrogen zarra na ruwa kwayoyin da oxygen zarra na carbonyl kungiyar.

A polarity da kwayoyin kafa ta daban-daban kwayoyin halitta, za a iya quantitatively bayyana ta a yawan da ake kira dipole lokacin. Kwayar Komayya kafa ta guda kwayoyin halitta ba iyakacin duniya ba ta kuma da dipole lokacin. Vector dipole lokacin directed zuwa kashi tsaye a cikin lokaci-lokaci tebur (daya lokaci) zuwa dama. Idan kwayoyin da aka hada da kwayoyin halitta na daya subgroup, da electron yawa za su matsawa zuwa cikin kashi tare da wani karami jerin lambar. Mafi yawa daga cikin hydrocarbons ba dipole lokacin ko ta girma ne musamman kananan, amma shi ne yafi hakan aldehydes, wanda kuma ya bayyana cikin jiki Properties na aldehydes.