Alkanes, alkenes, alkynes yog cov tshuaj organic. Tag nrho cov ntawm lawv yog tsim los ntawm cov tshuaj xws li carbon thiab hydrogen. Alkanes, alkenes, alkynes yog cov tshuaj sib xyaw ua ke uas koom nrog pawg ntawm hydrocarbons.
Nyob hauv kab lus no peb yuav saib alkynes.
Qhov no yog dab tsi?
Cov tshuaj no tseem hu ua acetylenic hydrocarbons. Cov qauv ntawm alkynes muab rau muaj cov pa roj carbon thiab hydrogen atoms hauv lawv cov molecules. Cov mis mos dav dav rau acetylenic hydrocarbons yog: C H2n-2. Qhov yooj yim tshaj plaws alkyne yog ethylene (acetylene). Nws muaj cov tshuaj formula nram qab no - С2Н2. Alkynes kuj suav nrog propyne nrog cov mis C3H4. Tsis tas li ntawd, butine (C4H6), pentine (C5 H8), hexine (C6H10), heptin (C7Н 12), octine (С8Н14), tsis muaj (С 9 Н16), Decin (С10Н18), thiab lwm yam. Txhua hom alkynes muaj cov yam ntxwv zoo sib xws. Cia wb mus saib lawv.
Lub cev muaj zog ntawm alkynes
Raws li lawv lub cev yam ntxwv, acetylenehydrocarbons zoo li alkenes.
Raws li ib txwm muaj, alkynes, uas nws cov molecules muaj los ntawm ob mus rau plaub cov pa roj carbon atoms, muaj lub xeev gaseous ntawm kev sib sau. Cov uas nyob hauv nws cov molecules muaj los ntawm tsib mus rau 16 carbon atoms, nyob rau hauv ib txwm ua kua. Cov uas nws cov molecules muaj 17 los yog ntau dua atoms ntawm cov tshuaj no yog cov khib nyiab.
Alkynes yaj thiab boil ntawm qhov kub siab tshaj alkanes thiab alkenes.
Solubility hauv dej yog negligible, tab sis me ntsis siab dua cov alkenes thiab alkanes.
Solubility hauv cov kuab tshuaj organic yog siab.
Cov alkyne uas siv dav tshaj plaws, acetylene, muaj cov khoom hauv qab no:
- tsis muaj xim;
- tsis tsw tsw;
- nyob rau hauv ib txwm muaj yog nyob rau hauv lub gaseous aggregate xeev;
- yog tsawg dua huab cua;
- boiling point - rho tawm 83.6 degrees Celsius;
tshuaj lom neeg ntawm alkynes
Nyob rau hauv cov tshuaj no, cov atoms txuas los ntawm ib tug triple daim ntawv cog lus, uas piav txog lawv lub ntsiab zog. Alkynes nkag mus rau hauv cov tshuaj tiv thaiv ntawm hom no:
- hydrogenation;
- halogenation;
- hydration;
- burning.
Yhydrohalogenation;
Cia peb saib lawv ib leeg.
Hydrogenation
Cov tshuaj lom neeg ntawm alkynes tso cai rau lawv nkag mus rau hauv cov tshuaj tiv thaiv ntawm hom no. Qhov no yog ib hom tshuaj sib cuam tshuam uas cov molecule ntawm cov khoom txuas ntxiv hydrogen atoms rau nws tus kheej. Ntawm no yog ib qho piv txwv ntawm xws li tshuaj tiv thaiv nyob rau hauv cov ntaub ntawv ntawm propyne:
2H2 + C3H4=C3N8
Cov tshuaj tiv thaiv no tshwm sim hauv ob kauj ruam. Ntawm thawj propyne molecule txuas ob lub hydrogen atoms thiab ntawm qhov thib ob - tib tus lej.
Halogenation
Qhov no yog lwm cov tshuaj tiv thaiv uas yog ib feem ntawm cov tshuaj lom neeg ntawm alkynes. Yog li ntawd, acetylenic hydrocarbon molecule txuas halogen atoms. Cov tom kawg suav nrog cov khoom xws li chlorine, bromine, iodine, thiab lwm yam.
Ntawm no yog ib qho piv txwv ntawm qhov kev tshwm sim ntawm ethine:
22 + 2СІ2=С2 N2SI4
Cov txheej txheem tib yam yog ua tau nrog lwm cov acetylenic hydrocarbons.
Y
Hydrohalogenation
Qhov no kuj yog ib qho ntawm cov tshuaj tiv thaiv tseem ceeb uas nkag mus rau hauv cov tshuaj lom neeg ntawm alkynes. Nws nyob hauv qhov tseeb tias cov tshuaj cuam tshuam nrog cov tshuaj xws li HCI, HI, HBr, thiab lwm yam. Cov tshuaj lom neeg no tshwm sim hauv ob theem. Cia peb saib cov tshuaj tiv thaiv no siv ethine ua piv txwv:
С2Н2 + NSI=С2Н 3
С2Н2СІ + NSI=С2Н 4SI2
Hydration
Qhov no yog tshuaj tiv thaiv uas cuam tshuam nrog dej. Nws kuj tshwm sim hauv ob theem. Cia peb saib nws nrog ethin ua piv txwv:
H2O + C2H2=C 2 H3OH
Cov tshuaj uas tsim tom qab thawj theemCov tshuaj tiv thaiv hu ua vinyl cawv.
Vim qhov tseeb tias, raws li txoj cai Eltekov, OH pab pawg ua haujlwm tsis tuaj yeem nyob ntawm ib sab ntawm ob daim ntawv cog lus, kev hloov pauv ntawm cov atoms tshwm sim, vim tias acetaldehyde yog tsim los ntawm vinyl cawv.
Cov txheej txheem ntawm hydration ntawm alkynes kuj hu ua cov tshuaj tiv thaiv Kucherov.
Combustion
Qhov no yog cov txheej txheem ntawm kev sib cuam tshuam ntawm alkynes nrog oxygen ntawm qhov kub thiab txias. Xav txog kev combustion ntawm cov tshuaj ntawm pab pawg no siv acetylene ua piv txwv:
2C2N2 +2O2=2N2 O + 3C + CO2
Nrog cov pa ntau dhau, acetylene thiab lwm yam alkynes hlawv yam tsis muaj cov pa roj carbon. Hauv qhov no, tsuas yog carbon oxide thiab dej tso tawm. Ntawm no yog qhov sib npaug rau cov tshuaj tiv thaiv uas siv propyne ua piv txwv:
4O2 + C3N4=2N2 O + 3CO2
Kev sib xyaw ntawm lwm cov acetylenic hydrocarbons kuj tshwm sim zoo ib yam. Qhov tshwm sim yog dej thiab carbon dioxide.
Lwm cov tshuaj tiv thaiv
Tsis tas li, acetylenes tuaj yeem ua rau cov ntsev ntawm cov hlau xws li nyiaj, tooj liab, calcium. Hauv qhov no, hydrogen hloov los ntawm cov hlau atoms. Xav txog hom tshuaj tiv thaiv no siv piv txwv ntawm acetylene thiab silver nitrate:
С2Н2 + 2AgNO3=Ag2C2 + 2NH 4NO3 + 2H2O
Lwm cov txheej txheem nthuav dav uas cuam tshuam nrog alkynes yog Zelinsky cov tshuaj tiv thaiv. Qhov no yog qhov tsim ntawm benzene los ntawm acetylene thaum nws yog rhuab mus rau 600 degrees Celsius.nyob rau hauv lub xub ntiag ntawm activated charcoal. Qhov sib npaug ntawm cov tshuaj tiv thaiv no tuaj yeem qhia tau raws li hauv qab no:
3S2N2=S6N6
Alkyne polymerization tseem ua tau - cov txheej txheem ntawm kev sib txuas ob peb lub molecules ntawm ib yam khoom rau hauv ib lub polymer.
Tau txais
Alkynes, cov tshuaj tiv thaiv uas peb tau tham saum toj no, tau txais hauv chav kuaj los ntawm ntau txoj hauv kev.
thawj yog dehydrohalogenation. Cov kev sib npaug sib npaug zoo li qhov no:
C2H4Br2 2KON=С2 N2 + 2N2O + 2KBr
Txhawm rau ua tiav cov txheej txheem zoo li no, nws yog qhov yuav tsum tau ua kom sov cov reagents, ntxiv rau ntxiv ethanol ua catalyst.
Nws kuj tseem tuaj yeem tau txais alkynes los ntawm cov tshuaj inorganic. Nov yog ib qho piv txwv:
CaC2 + H2O=C2H 2 + 2Ca(OH)2
Txoj kev tom ntej kom tau txais alkynes yog dehydrogenation. Nov yog ib qho piv txwv ntawm cov tshuaj tiv thaiv no:
2CH4=3H2 + C2H2
hom tshuaj tiv thaiv no tuaj yeem tsim tsis yog ethylene xwb, tab sis kuj muaj lwm yam acetylene hydrocarbons.
Siv alkynes
Qhov yooj yim tshaj plaws alkyne, ethylene, yog qhov siv dav tshaj plaws hauv kev lag luam. Nws yog dav siv hauv kev lag luam tshuaj.
- Xav tau acetylene thiab lwm yam alkynes los hloov lawv mus rau lwm cov organic tebchaw xws li ketones, aldehydes, cov kuab tshuaj thiabLwm yam
- Nws tseem tuaj yeem tau txais cov tshuaj los ntawm alkynes uas siv los tsim cov roj hmab, polyvinyl chloride, thiab lwm yam.
- Acetone tuaj yeem tau txais los ntawm propyne los ntawm Kucherov cov tshuaj tiv thaiv.
- Ntxiv rau, acetylene yog siv los tsim cov tshuaj xws li acetic acid, aromatic hydrocarbons, ethyl cawv.
- Acetylene kuj yog siv los ua cov roj uas muaj cua sov heev ntawm combustion.
- Tsis tas li, cov tshuaj tiv thaiv ethine yog siv los vuam hlau.
- Tsis tas li ntawd, kev siv cov pa roj carbon monoxide tuaj yeem tau siv acetylene.
- Kuj, cov tshuaj no siv rau hauv cov khoom siv tus kheej.
- Acetylene thiab ib tug xov tooj ntawm lwm cov hydrocarbons ntawm pab pawg no yog siv los ua foob pob ua ntxaij roj vim lawv kub ntawm combustion.
Qhov no xaus kev siv alkynes.
Zoo kawg
Raws li qhov kawg, ntawm no yog lub rooj luv luv ntawm cov khoom ntawm acetylenic hydrocarbons thiab lawv cov khoom.
| Reaction name | Kev piav qhia | piv txwv equation |
| Halogenation | Cov tshuaj tiv thaiv ntxiv ntawm halogen atoms (bromine, iodine, chlorine, thiab lwm yam) los ntawm acetylenic hydrocarbon molecule | C4H6 + 2I2=С4 N6I2 |
| Cov tshuaj tiv thaiv ntawm qhov sib ntxiv ntawm hydrogen atoms los ntawm alkyne molecule. tshwm sim hauv ob theem. |
C3H4 +N2=S3N6 C3H6 + H2=C3N8 |
|
| Hydrohalogenation | Cov tshuaj tiv thaiv ntxiv ntawm hydrohalogens (HI, HCI, HBr) los ntawm acetylenic hydrocarbon molecule. tshwm sim hauv ob theem. |
C2H2 + HI=C2H3 I C2H3I + HI=C2H 4 IIII |
| Hydration | Reaction raws li kev cuam tshuam nrog dej. tshwm sim hauv ob theem. |
C2N2 + H2O=C 2 H3OH C2H3OH=CH3-CHO |
| Complete oxidation (combustion) | Kev sib cuam tshuam ntawm acetylene hydrocarbon nrog oxygen ntawm qhov kub siab. Qhov tshwm sim yog carbon oxide thiab dej. |
2C2H5 + 5O2=2H2 O + 4CO2 2C2N2 + 2O2=N2 O + CO2 + 3C |
| Reactions nrog hlau ntsev | Muaj nyob rau hauv qhov tseeb tias hlau atoms hloov hydrogen atoms hauv cov molecules ntawm acetylene hydrocarbons. | С2Н2 + AgNO3=C2Ag2 + 2NH 4NO3 + 2H2O |
Alkynes tuaj yeem tau txais hauv chav kuaj hauv peb txoj kev:
- los ntawm cov tshuaj inorganic;
- by dehydrogenation ntawm cov organic teeb meem;
- waydehydrohalogenation ntawm cov organic tshuaj.
Yog li peb tau txiav txim siab tag nrho cov yam ntxwv ntawm lub cev thiab tshuaj lom neeg ntawm alkynes, txoj hauv kev rau lawv cov khoom, kev siv hauv kev lag luam.
