Carboxylic acids lub zog. Ntsev ntawm carboxylic acids

Yuav luag tag nrho cov tsev muaj vinegar. Thiab feem ntau cov neeg paub hais tias nws yog raws li acetic acid. Tab sis nws yog los ntawm cov tshuaj taw tes ntawm view? Yuav ua li cas lwm tus organic tebchaw nyob rau hauv no series muaj thiab dab tsi yog lawv cov yam ntxwv? Sim kom to taub txog qhov teeb meem no thiab mus xyuas marginal monobasic carboxylic acid. Tshwj xeeb tshaj yog nyob rau hauv lub tsev yog siv tsis tau tsuas yog acetic, tab sis kuj ob peb lwm, thiab tsuas yog derivatives ntawm cov acids nyob rau hauv kev yog heev qhua nyob rau hauv txhua txhua lub tsev.

Cov chav kawm ntawv ntawm carboxylic acids: ib tug general txheej txheem cej luam

Los ntawm lub standpoint ntawm science Science News for KIDS, rau cov hoob kawm no ntawm tebchaw xws li cov pa molecules uas muaj ib tug kev grouping ntawm atoms - ib tug carboxyl functional ib pawg. Nws muaj daim ntawv -COOH. Yog li, cov kev mis uas muaj tag nrho cov kev txwv monobasic carboxylic acid, yog raws li nram no: R-COOH, nyob rau R - yog ib tug particle radical, uas tej zaum yuav muaj xws li tej xov tooj ntawm cov pa roj carbon atoms.

Raws li rau qhov no, lub ntsiab txhais ntawm no hauv chav kawm ntawv ntawm tebchaw yuav muab hais tias. Carboxylic acid - yog oxygenated organic molecules uas muaj xws li ib los yog ntau functional pawg -COOH - carboxyl pawg.

Qhov tseeb hais tias cov tshuaj yog precisely rau acids, piav txog cov kev mus ncig ntawm lub hydrogen atom nyob rau hauv lub carboxyl. Lub electron ceev yog unevenly faib, txij li thaum cov pa - lub feem ntau electronegative pab pawg neeg. Los ntawm no kev sib raug zoo cov O-H xav polarized thiab hydrogen yuav tsis tshua muaj neeg lam tau lam ua. Nws yuav muab tau yooj yim phua tawm, nkag mus rau hauv tshuaj tshua. Yog li ntawd acid coj ntsuas muab ib tug zoo xws li cov tshuaj tiv thaiv:

• phenolphthalein - tsis muaj kob;
• litmus - liab;
• universal - liab;
• lub Methyl - liab thiab lwm tus neeg.

Vim lub hydrogen atom, carboxylic acid sau oxidizing zog. Txawm li cas los, lub xub ntiag ntawm lwm yam atoms tso cai rau lawv mus rov qab thiab koom tes nyob rau hauv ntau ntau lwm yam kev sib tshuam.

kev faib

Muaj ntau ntau lub ntsiab yam ntxwv, uas yog muab faib mus rau hauv pab pawg ntawm cov carboxylic acid. Cov Thawj zaug ntawm lawv - yog qhov xwm ntawm tus radical. Raws li qhov no tau txawv:

• Alicyclic acid. Piv txwv li: quinic.
• Aromatic. Piv txwv li: benzoic.
• Aliphatic. Piv txwv li: acetic acid, acrylic acid, oxalic acid, thiab lwm tus neeg.
• Heterocyclic. Piv txwv li: nicotine.

Yog hais tias peb tham txog kev mus nyob rau hauv lub molecule, ob pab neeg ntawm acids yuav tsum tau qhia:

• txwv - tag nrho cov ties xwb, ib;
• unsaturated - nyob rau hauv lub xub ntiag ntawm ob, ib los yog ntau yam.

Nws kuj yog ib tug kos npe rau ntawm kev faib yuav pab raws li functional pawg. Yog li ntawd, muaj cov nram no.

1. Monobasic - tsuas yog ib -COOH pab pawg neeg. Piv txwv li: formic, stearic, butyric, valeric, thiab lwm tus neeg.
2. Dibasic - feem, lub ob COOH pawg. Piv txwv li: oxalic acid, malonic acid, thiab lwm tus neeg.
3. Multibasic - citric, lactic, thiab lwm tus neeg.

Tom qab ntawd nyob rau hauv no tsab xov xwm peb yuav tsuas txwv monobasic carboxylic acids, aliphatic.

Keeb kwm ntawm foundations

Winery thrived nrog lub ancient lub sij hawm. Raws li yog lub npe hu, ib qho ntawm nws khoom - acetic acid. Yog li ntawd lub keeb kwm ntawm lub koob meej ntawm no hauv chav kawm ntawv ntawm tebchaw muaj cov hauv paus hniav ntawm lub sij hawm ntawm Robert Boyle thiab Ioganna Glaubera. Txawm li cas los, nws twb tsis tau mus nrhiav tau tawm rau ib ntev lub sij hawm nrog cov tshuaj xwm ntawm cov molecules.

Rau ib ntev lub sij hawm yeej vitalists views, uas tsis pom zoo qhov tseem ntawm lub tsim ntawm organic tsis muaj nyob beings. Tab sis nyob rau hauv 1670 AD Ray tswj kom tau tus thawj heev tus neeg sawv cev - methane los yog formic acid. Nws ua li no los ntawm cua sov rau cov hwj nyob rau hauv lub ntsaum.

Tom qab ntawd ua hauj lwm ntawm kws tshawb fawb thiab Kolbe Berzelius pom tau synthesizing cov tebchaw los ntawm inorganic tshuaj (distillation hluav ncaig). Raws li ib tug tshwm sim acetic acid twb tau. Yog li lub carboxylic acid tau kawm (lub zog, qauv) thiab pib ntawm qhib ntawm tag nrho cov lwm cov neeg hauv lub series ntawm aliphatic tebchaw.

lub zog

Niaj hnub no, ib tug tshawb kom ntxaws txog tag nrho lawv cov neeg sawv cev. Rau txhua tus ntawm cov yam ntxwv yuav pom nyob rau hauv tag nrho cov tsis, xws li cov kev siv nyob rau hauv kev lag luam thiab ua nyob rau hauv cov xwm. Peb yuav xyuas li cas yuav muab lub carboxylic acids, lub cev zog ntawm lwm yam tsis.

Yog li ntawd, muaj ntau ntau yooj yim yam ntxwv tsis.

1. Yog hais tias cov xov tooj ntawm cov pa roj carbon atoms nyob rau hauv cov saw hlau tsis pub tshaj tsib, nws dheev daws qhov teebmeem ntawd, rooj noj thiab volatile kua. Saum toj no lub tsib - hnyav, oily tshuaj, ntau - ib qho nyuaj, waxy.
2. Cov kev ceev ntawm lub thawj ob tug mej zeej yog ntau tshaj ib tug. Tag nrho lwm cov sib zog tshaj dej.
3. Kub point: ntau dua qhov lub saw, ntau dua qhov tau. Qhov ntau branched qauv, rau hauv qab no.
4. Melting point: nyob rau hauv lub parity ntawm tus xov tooj ntawm cov pa roj carbon atoms nyob rau hauv cov saw hlau. Y yog txawm ntau dua nyob rau hauv khib hauv qab no.
5. Nyob rau hauv dej, nws yaj zoo heev.
6. Yog muaj peev xwm ntawm txoj kev muaj zog hydrogen bonds.

Tej yam no yog piav los ntawm cov qauv ntawm cov symmetry, thiab chaw pib lub ntxaij ntoo qauv, nws lub zog. Qhov ntau yooj yim thiab kev molecule, lub saum toj no qhia tau hais tias muab ib tug carboxylic acid. Lub cev thaj chaw ntawm cov tebchaw pub rau txhais tau lub teb thiab lawv txoj kev siv nyob rau hauv kev lag luam.

tshuaj zog

Raws li peb tau xaiv saum toj no, acid cov ntaub ntawv tej zaum yuav qhia txawv zog. Lawv tshua yog ib qho tseem ceeb rau cov muaj synthesis ntawm ntau lub tebchaw. Txhais lub tseem ceeb tshaj plaws tshuaj zog uas yuav ua tau monobasic carboxylic acid.

1. ^{Dissociation: R-COOH = RCOO - +} H +.
   
2. Teev acidic zog, i.e. ua num ua ke nrog qhov yooj yim oxides thiab lawv hydroxides. Nrog yooj yim co reacted los ntawm tus txheej txheem txheej txheem (i.e., tsuas yog cov uas yuav muaj hydrogen nyob rau hauv lub electrochemical series).
3. Muaj ntau zog acids (inorganic) behaves raws li ib puag.
4. Peev xwm txo kom cov thawj cawv.
5. Tshwj xeeb cov tshuaj tiv thaiv - esterification. No sis nrog alcohols tsim tau ib txoj khoom - ester.
6. decarboxylation cov tshuaj tiv thaiv, xws li cov tshem tawm ntawm lub compound carbon dioxide molecule.
7. Peev xwm ntawm reacting nrog halides ntawm hais xws li phosphorus thiab sulfur.

Obviously, raws li multifaceted carboxylic acid. Lub zog, raws li zoo raws li cov tshuaj, yog heev ntau haiv neeg. Nyob rau hauv tas li ntawd, nws yuav tsum tau hais tias nyob rau hauv Feem ntau cov zog raws li acids, tag nrho cov organic molecules theej tsis muaj zog piv rau lawv tej inorganic counterparts. Lawv dissociation constants tsis pub tshaj tus nqi ntawm 4.8.

Txoj kev rau cov kev npaj

Muaj ntau ntau yooj yim txoj kev uas yuav tau txais marginal carboxylic acid.

1. Nyob rau hauv lub laboratory nws yog ua los ntawm oxidation:

• alcohols;
• aldehydes;
• alkyne;
• NTSHAV;
• kev puas tsuaj ntawm alkenes.

2. Hydrolysis:

• esters;
• nitrites;
• amides;
• trigalogenalkanov.

3. Decarboxylation - tshem tawm ntawm lub CO ₂ molecule.

4. Nyob rau hauv industrial synthesis yog nqa tawm los ntawm oxidation ntawm hydrocarbons nrog ntau carbon atoms nyob rau hauv cov saw hlau. Cov txheej txheem yog nqa tawm nyob rau hauv ob peb theem rau paib ib plurality ntawm byproducts.

5. Ib txhia kev acids (formic, acetic, butyric, valeric, etc.) npaj los ntawm ib qho kev siv tej yam ntuj tso khoom xyaw.

Basic compound txwv carboxylic acids: ntsev

Ntsev ntawm carboxylic acids - ib qho tseem ceeb tebchaw siv nyob rau hauv qhov kev lag luam. Lawv ua tau los ntawm cov kev sis raug zoo ntawm lub yav tas nrog:

• co;
• yooj yim oxides;
• amphoteric oxides ;
• alkalis;
• amphoteric hydroxides.

Tshwj xeeb yog ib qho tseem ceeb nyob rau hauv lawv yog cov neeg uas raug tsim ntawm alkali hlau sodium thiab potassium thiab lub siab tsis pub tshaj acids - palmitic, stearic. Tom qab tag nrho cov ntawm no lub sis - xab npum, kua thiab khoom.

xab npum

Yog li, nyob rau hauv cov ntaub ntawv ntawm xws li ib tug tshuaj tiv thaiv: 2C ₁₇ H ₃₅ -COOH + 2Na = 2C ₁₇ H ₃₅ COONa + H _2,

lub resulting khoom - sodium stearate - nws yog los ntawm qhov ib tug qub xab npum siv rau ntxhua khaubncaws.

Yog hais tias palmitic acid twb hloov, thiab cov poov tshuaj hlau rau nws yuav tig poov tshuaj palmitate - xab npum ntxuav ob txhais tes. Yog li ntawd, peb yuav confidently qhia hais tias cov ntsev ntawm carboxylic acids - qhov no yog ua tau ib qho tseem ceeb sib txuas ntawm organic xwm. Lawv raug thiab siv ntawm ib tug colossal nyob rau hauv scale. Yog hais tias koj xav txog tej yam yuav ua li cas npaum li cas xab npum siv txhua tus neeg nyob ntiaj teb, nws yog ib qho yooj yim mus xav txog tej yam thiab cov dos.

Esters ntawm carboxylic acids

Ib tug tshwj xeeb cov pab pawg neeg ntawm cov tebchaw, uas nws muaj nws qhov chaw nyob rau hauv lub labeling ntawm cov organic tebchaw. Qhov no hauv chav kawm ntawv ntawm esters. Lawv tsim los ntawm cov tshuaj tiv thaiv ntawm carboxylic acids nrog alcohols. Title xws li kev sib tshuam - lub esterification cov tshuaj tiv thaiv. General saib yuav sawv cev los ntawm lub kab zauv:

^{R, -COOH + R "-OH =} R, -COOR" + H ₂ O.

Khoom nrog ob tug radicals yog ib tug ester. Obviously, raws li ib tug tshwm sim ntawm cov tshuaj tiv thaiv ib tug carboxylic acid, haus dej cawv, ester thiab dej tau undergone tseem ceeb cov kev hloov. Yog li, hydrogen yoojyim los ntawm lub acid molecules nyob rau hauv daim ntawv ntawm ib tug ntawv thiab raws li cov hydroxy pab pawg neeg los ntawm ib tug dej cawv raug phua tawm. Raws li ib tug tshwm sim, cov dej molecule yog tsim. Grouping seem rau lub acid radical yuav siv sij hawm los ntawm lub cawv txoj kev ester molecule.

Yuav ua li cas yog li ntawd ib qho tseem ceeb cov tshuaj li cas thiab lub coj mus muag tus nqi ntawm lawv cov khoom? Qhov no yog hais tias esters yog siv raws li:

• kev pab noj haus;
• flavors;
• puas tivthaiv ntawm naj hoom;
• kuab tshuaj;
• tivthaiv varnishes, xim tsev, yas;
• tshuaj thiab thiaj li nyob.

Nws yog tseeb hais tias lub tshav pob ntawm kev siv yog dav txaus mus nrhiav pov thawj ntau lawm nyob rau hauv kev ua lag luam.

Ethanoic acid (acetic)

Qhov no txwv monocarboxylic aliphatic acid, uas yog ib qho ntawm feem nrov nyob rau hauv cov nqe lus ntawm ntau lawm thoob ntiaj teb. Nws mis - CH ₃ COOH. Tej loj heev nws tshuav nqi nws lub zog. Tom qab tag nrho, lub tshav pob ntawm kev siv yog dav heev.

1. Nws yog ib tug khoom noj khoom haus additive nyob rau hauv E-260 code.
2. Nws yog siv nyob rau hauv cov zaub mov kev lag luam rau preservation.
3. Nws yog siv nyob rau hauv cov tshuaj rau lub synthesis ntawm medicaments.
4. Tivthaiv nyob rau hauv qhov kev npaj ntawm odoriferous tebchaw.
5. Hnyav.
6. Koom nyob rau hauv tus txheej txheem ntawm printing, dyeing fabrics.
7. Cov tsim nyog cheebtsam hauv tshuaj syntheses tshua plurality ntawm tshuaj.

Nyob rau hauv ib lub neej ntawm nws 80-feem pua cov kua hu ua acetic essence, thiab yog hais tias dilute nws mus rau 15%, uas koj tau txais yog vinegar. Net 100% glacial acetic acid yog hu ua.

formic acid

Cov thawj thiab nyuaj tus neeg sawv cev ntawm cov hoob kawm no. Formula - HCOOH. Tsis tas li ntawd ib tug khoom noj khoom haus additive nyob rau hauv E-236 code. Nws tej yam ntuj tso qhov chaw:

• ntsaum thiab muv;
• nettles;
• koob;
• txiv hmab txiv ntoo.

Lub ntsiab qhov chaw ntawm qhov kev siv:

• rau lub preservation thiab kev npaj ntawm cov tsiaj pub;
• Nws yog siv rau cov kev tswj ntawm cab;
• rau dyeing fabrics etchant qhov chaw;
• raws li ib tug hnyav;
• bleach;
• nyob rau hauv cov tshuaj - kom tuaj tua kab seev thiab khoom;
• los tsim cov pa roj carbon monoxide nyob rau hauv cov kev kuaj.

Tsis tas li ntawd nyob rau hauv phais ntawm no acid tshuaj yog siv raws li antiseptics.