Acetic acid

Ko Organic monobasic carboxylic acid, da kwayoyin da wanda ya ƙunshi biyu carbon kwayoyin zarra da wani carboxyl kungiyar (samu da sunan saboda shi kunshi da carbonyl da carboxyl kungiyoyin), da ake kira ethane (da misalin tare da alkane da wannan adadin carbon atoms) ko acetic acid. Ta, kamar duk ƙananan aliphatic membobin wannan aji na gudanar da mahadi, yana da wani pungent wari. Its sinadaran dabara za a iya rubuta kamar: CH3COOH. A yanayi na yanayi a colorless ruwa. Yawa - 1.05 g / cm³. Matauni taro ne daidai 60,05 g / mol. Yana narke a zazzabi na 16,75 ° C (kasa da ƙarfafa lu'ulu'u kama da kankara, don haka ya kira kankara). Tafasa a zazzabi na 118,1 ° C. A Refractive index ne daidai to 1.372.

Wakilai daga wannan aji na gudanar da mahadi ne weaker fiye hydrochloric ko sulfuric acid, amma idan aka kwatanta da carbonic acid, mafi tsanani shi ne acetic acid. A sunadarai Properties ƙaddara da membobinta na carbonyl kwayoyin da hydroxyl kungiyoyin. Su tasiri da karfi da juna cewa sinadaran Properties daga cikin abu ne kawai zuwa kananan har reminiscent na da kaddarorin carbonyl mahadi (aldehydes, amides, ketones, esters) ko alcohols. Ionization auku O-H Hadin saboda ja electrons carbonyl kungiyar. Saboda haka, dangane da sauƙin dissociate fiye da a alcohols. Hijirar na electrons daga hydroxyl kungiyar zuwa carbonyl partially rage carbon zarra na tabbatacce cajin, yin shi da wuya su kai farmaki shi tare da nucleophile. Saboda haka, da yawa abubuwa hulda sauƙi tare da carbonyl mahadi ba su amsa tare da CH3COOH.

Don a kananan har acetic acid iya dissociate ta samar da hydrogen ions: CH3COOH + H2O ↔ CH3CO2ˉ + H3O +. An halin neutralization tare da kwasfansu, wanda a cikin sa gishiri samuwar: NaOH + CH3COOH → CH3COONa + H2O . Carboxylic acid salts ne kullum ruwa mai narkewa. Wannan yanayin facilitates hakar daga halitta kafofin. Saboda haka acid sun kasance daga cikin na farko ware daga kwayoyin abubuwa. Alal misali, ethane aka samu daga ruwan tsami. Strong hydrogen shaidu aka kafa tsakanin kwayoyin na CH3COOH, game da shi, a cikin kwayoyin kaushi, kuma a cikin gas lokaci, ya wanzu a matsayin dimer.

Acetic acid da kuma ruwa ne miscible a duk rabbai. Ya canza da kaddarorin dangane da natsuwa. Moderately m zuwa karafa, ciki har da baƙin ƙarfe, magnesium da kuma tutiya. Wannan yã'yan hydrogen da gishiri-kira acetates: MG + 2 CH3COOH → (CH3COO) 2Mg + H2 ↑. Tun aluminum Forms wani acid-resistant passivation film na aluminum oxide, da aluminum tank, tare da bakin karfe tankuna amfani for kai CH3COOH.

A masana'antu, acetic acid aka samar da hadawan abu da iskar shaka na wani aldehyde na wannan sunan: 2CH3COH + O2 → 2CH3COOH. Daga 800 kg na aldehyde shirya ton CH3COOH. Amma kwanan nan more hanya domin samar da - a ruwa lokaci hadawan abu da iskar shaka na butane da iska oxygen a zazzabi na 150-170 ° C da kuma matsa lamba na 50 atmospheres: CH3CH2CH2CH3 + 2O2 → 2CH3COOH + 2 H2O. A gaskiya ma, cikin amsawa ne yafi rikitarwa da nuna. Bayan acetic acid, ta fito da wani yawan byproducts. Duka wadannan hanyoyi suna tura daga (saboda mafi girma farashin man) da carbonylation na methanol: CO + CH3OH → CH3COOH. A tsari Saide a gaban mai kara kuzari wanda shi ne mai gishiri da azurfa, kuma promoters (activators) - iodide ions. Da ikon wasu kananan kwayoyin halitta suna fermented ethyl barasa, bi da hadawan abu da iskar shaka a CH3COOH, amfani da biochemical samar: C2H5OH + O2 → CH3COOH + H2O . A tsari ne sosai hadaddun da faruwa a dama, saukarwa.

Acetic acid ne kerarre daidai da Gost 19814-74 (roba da kuma sake halitta) Gost 18270-72 (high tsarki) da kuma Gost 61-75 (amsawa). Wannan shi ne wani muhimmin sinadaran reagent da kuma masana'antu sinadaran cewa ne, yafi amfani a samar, da ake amfani da robobi, roba zaruruwa, dyes, film da sauransu. Shi ne da albarkatun kasa domin samar da roba acetate wanda aka yi amfani da tsari na samun sevilene (as ethylene comonomer). A amfani da acetic acid saboda da sinadaran da jiki Properties. CH3COOH salts ne mordants cewa bauta ga kayyade da dyes a kan zare.

A gidaje diluted acetic acid da aka yi amfani da sau da yawa a matsayin descaling wakili. A cikin masana'antun sarrafa kayayyakin abinci da shi da ake amfani da karkashin code E260 abinci Additives kamar acidity kayyadewa da kuma matsayin condiment. Abinci ƙari yarda da amfani a cikin EU, Amurka, Australia da kuma New Zealand. A cikin masana'antun sarrafa kayayyakin abinci da shi da ake amfani da pickling kayayyakin a cikin nau'i na vinegar da taro na CH3COOH a ruwa na 3 zuwa 15% ko vinegar da wani taro sulusi da murabba'i na asali abu na 70%. Da dama esters na acetic acid amfani a cikin confectionery masana'antu.