El formic acid o Iasidi yeMethanoic yeyona khompawundi ilula nencinane kuzo zonke iiasidi eziphilayo. Inemolekyuli ye-HCOOH ene-athomu enye kuphela ye-hydrogen edityaniswe kwi-athomu yekhabhoni. Igama layo livela kwigama elithi formica, elithetha imbovane ngesiLatini. Yikhompawundi ebaluleke kakhulu kwihlabathi lekhemistri kwaye isetyenziswa ngokubanzi namhlanje.
Ngenxa yesi sizathu, siza kunikela eli nqaku ukukuxelela yonke into okufuneka uyazi malunga ne-asidi ye-formic, iimpawu zayo kunye nokubaluleka.
Iimpawu eziphambili
Iingcali zendalo zenkulungwane yeshumi elinesihlanu zafumanisa ukuba iintlobo ezithile zezinambuzane (izibulali-zinambuzane), ezifana Iimbovane, iintubi, iinyosi nooqongqothwane, bakhupha le khompawundi eyenza ukuluma kwabo kube buhlungu. Ukongezelela, ezi zinambuzane zisebenzisa le ngqungquthela njengendlela yokuhlasela, ukukhusela kunye nokubonakaliswa kweekhemikhali.
Anamadlala anetyhefu akhupha oku kunye nezinye iiasidi, ezifana ne-acetic acid, emzimbeni ngendlela yenkungu. I-asidi ye-Formic yomelele kune-acetic acid (CH3COOH); ngoko ke, inani elilinganayo le-asidi ye-formic echithwe emanzini iya kubangela isisombululo kunye ne-pH ephantsi.
Isazi ngendalo esiNgesi uJohn Ray iphumelele ukwahlulwa kwale khompawundi ngo-1671, ekhutshwe kwinani elikhulu leembovane. Ngakolunye uhlangothi, i-synthesis yokuqala eyimpumelelo yale ngqungquthela yenziwa yi-chemist yaseFransi kunye ne-physicist uJoseph Gay-Lussac usebenzisa i-hydrocyanic acid (HCN) njenge-reagent.
formic acid kwindalo
I-asidi ye-formic ingabakho kumanqanaba omhlaba, njengenxalenye ye-biomass okanye kwi-atmosfera, ithatha inxaxheba kuluhlu olubanzi lweempendulo zemichiza, inokufumaneka phantsi komhlaba, kwi-oyile okanye kwisigaba segesi kumphezulu wayo.
Ngokumalunga ne-biomass, izinambuzane kunye nezityalo zezona zivelisa le asidi. Xa amafutha efosili esitsha, avelisa iasidi yefomi eyigesi; ngoko ke, iinjini zemoto zikhulula le asidi emoyeni.
Nangona kunjalo, zininzi iimbovane eziphila emhlabeni; kunye nokuveliswa kwe-asidi ye-formic phakathi kwabo kungamawaka amaxesha amakhulu kunomlinganiselo we-methanoic acid eveliswa lishishini lomntu ngonyaka omnye. Imililo yasehlathini ikwangumthombo wegesi yefomic acid.
Phezulu phezulu, kwi-matrix eyinkimbinkimbi ye-atmospheric, iinkqubo ze-photochemical ze-synthesis ye-asidi ye-formic zenzeka. Ngeli xesha, ezininzi i-volatile organic compounds (VOCs) ziyancipha phantsi kwesenzo semitha ye-UV okanye i-oxidized yi-OH ye-radical mechanism. I-chemistry ye-atmospheric etyebileyo kunye nentsonkothileyo ikude kakhulu owona mthombo we-methanoic acid emhlabeni.
Ubume be-atomic ye-asidi ye-formic
Lo mzobo ungasentla ubonisa ubume besigaba segesi sedimer ye-asidi ye-asidi. Iingqukuva ezimhlophe zihambelana neeathom ze-hydrogen, ezibomvu kwiiathom ze-oxygen kwaye ezimnyama kwiiathom zekhabhoni.
Amaqela amabini anokubonwa kwezi molekyuli: ihydroxyl (-OH) kunye neformyl (-CH=O), ezikwaziyo ukwenza iibhondi zehydrogen. Olu nxibelelwano luluhlobo lwe-OHO, apho iqela le-hydroxyl liyi-H donor kunye neqela le-formyl ngumnikeli we-O.
Nangona kunjalo, i-H ebotshelelwe kwiiathom zekhabhoni ayinabo obu buchule. Ezi ntsebenziswano zinamandla kakhulu, kwaye i-hydrogen kwiqela le-OH i-acidic ngakumbi ngenxa ye-athomu ye-electron-i-H; Ngoko, le hydrogen ngakumbi uzinzisa ibhulorho. Ngenxa yoku ngasentla, i-asidi ye-formic ikhona njenge-dimer kwaye kungekhona njenge-molecule yomntu.
Njengoko iqondo lobushushu liyehla, i-dimer iqhelanisa iibhondi zayo ze-hydrogen ukwenza esona sakhiwo sizinzileyo nezinye ii-dimers, okukhokelela kumatyathanga e-alpha kunye ne-beta angenasiphelo e-methanoic acid. Esi sakhiwo sekristale Kuxhomekeke kwizinto eziguquguqukayo zomzimba ezisebenza kuyo, ezifana noxinzelelo kunye nobushushu.. Ngoko ke, ikhonkco iyaguqulwa. Ukuba uxinzelelo lonyuswa kumanqanaba agqithisileyo, amatyathanga axinzelelwe ngokwaneleyo ukuba athathwe njengepolymer ye-crystalline ye-asidi yefomi.
Propiedades
Siza kugxila ekuchazeni iimpawu eziphambili ze-formic acid:
- methanoic acid na ulwelo olungenambala kubushushu begumbi kunye nevumba elibukhali elibukhali. Inobunzima bemolekyuli obuyi-46g/mol, indawo yokunyibilika eyi-8,4ºC kunye neqondo lokubila elingu-100,8ºC, elingaphezulu kunalamanzi.
- Ixutywe namanzi kunye nezinyibilikisi zepolar eziphilayo ezifana ne-ether, i-acetone, i-methanol kunye ne-ethanol.
- Ngokuchasene noko, kwizinyibilikisi ezinevumba elimnandi njenge-benzene kunye ne-toluene, ayinyibiliki kakuhle kuba i-asidi ye-formic ine-athom zekhabhoni ezimbalwa kubume bayo.
- InepKa ye-3,77, ene-acidic ngaphezu kwe-acetic acid, enokuchazwa ngenxa yokuba iqela le-methyl libonelela ngoxinaniso lwe-electron kwi-athomu ye-carbon oxidized yi-oksijeni ezimbini. Oku kubangela ukuhla okuncinci kwi-acidity yeeprotons (CH3COOH, HCOOH).
- Emva kokuba i-asidi ikhutshiwe, iguqulelwa kwi formate anion HCOO-, esusa intlawulo embi phakathi kweeathom ezimbini zeoksijini. Ngoko ke, i-anion ezinzileyo kwaye ijongene ne-asidi ephezulu ye-asidi ye-formic.
Ukusetyenziswa kweFormic Acid
Ishishini lokutya nezolimo
Iyingozi njengemethanoic acid, isetyenziswe ekugxininiseni okwaneleyo njengento yokugcina ukutya ngenxa yempembelelo yayo ye-antibacterial. Ngenxa yesizathu esifanayo sokuba isetyenziswe kwezolimo, ikwanazo iimpawu ze-insecticidal. Ikwanazo nefuthe le-antiseptic kwingca kwaye inceda ukuthintela igesi yamathumbu kwizilwanyana zasefama.
Ishishini lelaphu kunye nezihlangu
Isetyenziswa kushishino olulukiweyo ukudaya kunye nokucokisa amalaphu kwaye mhlawumbi yeyona ndlela ixhaphakileyo yokusetyenziswa kwale asidi. I-asidi ye-Formic isetyenziselwa ukulungiswa kwesikhumba kunye nokuchithwa kwesi sixhobo nge isenzo sayo sokunciphisa. Ukuchithwa kwe-asidi ye-formic iguqulela kwi-anion ye-formate HCOO-, eyenza i-delocalizes intlawulo embi phakathi kwee-athom ezimbini ze-oksijini. Ngoko ke, i-anion ezinzileyo kwaye ijongene ne-asidi ephezulu ye-asidi ye-formic.
Ukhuseleko ezindleleni
Ukongeza kusetyenziso oluchaziweyo lwemizi-mveliso, izinto eziphuma kwifomati ye-asidi (ifomati) zisetyenziswa kwiindlela zasebusika eSwitzerland nase-Austria. ukunciphisa umngcipheko weengozi. Olu nyango lusebenza ngakumbi kunokusebenzisa ityuwa yetafile.
Ndiyathemba ukuba ngolu lwazi unokufunda ngakumbi malunga ne-asidi ye-formic, isakhiwo sayo kunye nokusetyenziswa kwayo.