Cov Hydrocarbon Compounds yog dab tsi?
Cov hydrocarbons yog ib pawg tseem ceeb tshaj plaws ntawm cov tshuaj lom neeg hauv lub neej niaj hnub no. Peb sib cuam tshuam nrog cov khoom lag luam los ntawm cov hydrocarbons yuav luag txhua hnub, los ntawm cov roj tsheb thiab cov roj ua noj rau cov roj av cav thiab txawm tias cov khoom siv raw rau cov yas. Vim yog lawv lub luag haujlwm tseem ceeb, kev nkag siab txog cov hydrocarbons, lawv cov qauv, hom, thiab kev siv yuav pab peb pom kev sib txuas ntawm chemistry thiab peb cov kev xav tau txhua hnub.
Kev Txhais Lus ntawm Cov Hydrocarbon Compounds
Hais yooj yim xwb, cov hydrocarbon yog cov tshuaj sib xyaw ua ke uas muaj ob lub ntsiab lus xwb: hydrogen (H) thiab carbon (C). Txawm hais tias muaj ob hom atoms xwb, cov hydrocarbons muaj ntau yam duab thiab hom. Qhov no yog vim tias cov carbon atoms tuaj yeem tsim cov saw ntev, ceg, nplhaib, thiab ib qho, ob npaug, lossis peb npaug. Lub peev xwm ntawm carbon no hu ua tetravalent (muaj plaub lub electrons valence uas tuaj yeem tsim plaub lub covalent bonds), uas tso cai rau kev tsim cov qauv nyuaj.
Nyob rau hauv xwm, cov hydrocarbons pom muaj ntau nyob rau hauv roj av, roj av, thee, thiab cov khoom ntawm cov kab mob thaum ub uas tau lwj mus ntau lab xyoo. Tsis tas li ntawd, cov hydrocarbons kuj tseem tuaj yeem tsim tau los ntawm kev tshuaj lom neeg hauv chav kuaj thiab kev lag luam.
Vim li cas Carbon thiab Hydrogen thiaj li tsim tau ntau yam sib xyaw?
Qhov tshwj xeeb ntawm cov hydrocarbons yog los ntawm qhov xwm txheej ntawm cov pa roj carbon uas yooj ywm. Cov pa roj carbon tuaj yeem:
1. Tsim cov kev sib txuas nrog lwm cov carbons (C–C), tsim cov saw hlau ncaj lossis ceg.
2. Tsim cov ntawv cog lus ib zaug, ob zaug thiab peb zaug, uas ua rau muaj qhov sib txawv ntawm kev ua haujlwm thiab kev ruaj khov.
3. Tsim cov qauv cyclic (rings), ob qho tib si rings yooj yim thiab rings nrog tus cwj pwm aromatic.
4. Tsim cov isomers, uas yog cov tshuaj uas muaj cov qauv molecular zoo ib yam tab sis cov atoms sib txawv. Isomers tuaj yeem hloov pauv cov yam ntxwv ntawm lub cev thiab tshuaj ntawm ib qho tshuaj.
Vim yog cov yam no, cov hydrocarbons yog lub hauv paus rau cov organic chemistry thiab ua lub luag haujlwm tseem ceeb ua cov khoom siv raw rau ntau yam khoom sib xyaw xws li cawv, aldehydes, ketones, carboxylic acids, thiab polymers.
Kev faib tawm ntawm Cov Hydrocarbon Compounds
Feem ntau, cov hydrocarbons muab faib ua ob pawg loj: aliphatic hydrocarbons thiab aromatic hydrocarbons. Txhua tus muaj cov pawg me tseem ceeb.
1. Cov roj aliphatic hydrocarbons
Cov aliphatic hydrocarbons yog cov hydrocarbons uas tsis muaj cov nplhaib aromatic. Pawg no tuaj yeem yog qhib-saw (ncaj lossis ceg) lossis tsis-aromatic. Aliphatic hydrocarbons raug muab faib ua peb hom tseem ceeb:
a. Alkanes (Cov Hydrocarbons Uas Ntim Tau)
Alkanes yog cov hydrocarbons uas tsuas muaj ib qho kev sib txuas ntawm cov carbon atoms (C–C). Vim tias lawv tsis muaj kev sib txuas ob npaug, alkanes hu ua saturated, txhais tau tias lawv muaj tus lej ntau tshaj plaws ntawm cov hydrogen atoms sib txuas rau cov carbon atoms.
– Cov mis dav dav ntawm alkanes: CₙH₂ₙ₊₂
– Piv txwv li: methane (CH₄), ethane (C₂H₆), propane (C₃H₈), butane (C₄H₁₀)
Cov alkanes tsis tshua muaj zog npaum li cov alkenes thiab alkynes. Txawm li cas los xij, lawv tseem ceeb heev rau kev ua roj, xws li methane hauv cov roj ntuj thiab octane hauv roj av.
b. Alkenes (Cov Hydrocarbons Tsis Muaj Sia)
Alkenes muaj tsawg kawg yog ib qho kev sib txuas ob npaug (C=C). Vim yog qhov kev sib txuas ob npaug, alkenes raug hu ua unsaturated.
- Cov mis dav dav ntawm alkenes (rau ib qho kev sib txuas ob npaug): CₙH₂ₙ
– Piv txwv li: ethene/ethylene (C₂H₄), propene (C₃H₆)
Alkenes muaj zog dua li alkanes thiab siv dav ua cov khoom siv raw hauv kev lag luam, piv txwv li ethylene los ua polyethylene (yas) thiab ntau yam khoom siv tshuaj lom neeg.
c. Alkynes (Cov Hydrocarbons Tsis Muaj Sia)
Alkynes muaj tsawg kawg yog ib qho triple bond (C≡C). Lawv kuj yog cov unsaturated hydrocarbons thiab feem ntau muaj kev cuam tshuam ntau dua li alkenes.
- Cov mis dav dav ntawm alkyne (rau ib qho triple bond): CₙH₂ₙ₋₂
– Piv txwv li: ethyne/acetylene (C₂H₂)
Acetylene feem ntau siv rau hauv kev lag luam vuam vim nws tsim cov nplaim kub thaum hlawv nrog oxygen.
2. Cov Hydrocarbons uas muaj ntxhiab tsw qab
Cov hydrocarbons uas muaj ntxhiab tsw qab yog cov tshuaj uas muaj cov nplhaib ntxhiab tsw qab, tshwj xeeb yog cov nplhaib benzene. Lawv cov qauv nplhaib tshwj xeeb muaj lub kaw lus electron delocalized, uas ua rau lawv ruaj khov.
– Piv txwv li: benzene (C₆H₆), toluene (C₇H₈), xylene (C₈H₁₀)
Cov tshuaj tsw qab siv dav dav ua cov kuab tshuaj thiab cov khoom siv raw hauv kev lag luam. Txawm li cas los xij, qee cov tshuaj tsw qab kuj muaj tshuaj lom thiab ua rau mob qog noj ntshav, yog li lawv siv yuav tsum tau saib xyuas.
Cov Khoom Siv Lub Cev ntawm Hydrocarbons
Feem ntau, cov hydrocarbons muaj ntau yam ntxwv ntawm lub cev:
1. Nonpolar, yog li nws nyuaj rau yaj hauv dej tab sis yaj hauv cov kuab tshuaj nonpolar xws li benzene lossis ether.
2. Yooj yim kub hnyiab, vim tias qhov kev sib xyaw ua ke ntawm cov hydrocarbons tsim cov zog ntau heev.
3. Lub ntsiab lus kub nce ntxiv thaum tus lej ntawm cov pa roj carbon atoms nce ntxiv, vim tias cov zog intermolecular (London forces) muaj zog dua hauv cov molecules loj dua.
4. Daim ntawv nyob ntawm qhov ntev ntawm cov saw hlau carbon: cov hydrocarbons luv luv feem ntau yog cov roj (piv txwv li methane), cov saw hlau nruab nrab yog cov kua (roj av), thiab cov saw hlau ntev tuaj yeem yog cov khoom khov (paraffin, asphalt).
Cov Tshuaj Tseem Ceeb hauv Hydrocarbons
Cov hydrocarbons tuaj yeem ua rau muaj ntau yam kev tshuaj lom neeg, suav nrog:
– Kev hlawv (oxidation): tsim CO₂ thiab H₂O (kev hlawv zoo meej) lossis CO thiab pa luam yeeb (kev hlawv tsis tiav). Piv txwv li: roj tsheb.
- Kev hloov pauv: feem ntau nyob rau hauv alkanes, piv txwv li cov tshuaj tiv thaiv nrog halogens (chlorination).
- Kev ntxiv: feem ntau nyob rau hauv alkenes thiab alkynes, piv txwv li ntxiv hydrogen (hydrogenation) los hloov cov pob zeb sib txuas ob npaug rau hauv ib qho pob zeb sib txuas.
– Kev ua kom cov polymerization zoo: cov molecule me me xws li ethylene sib xyaw ua ke los ua cov polymers loj xws li polyethylene.
- Kev tawg: kev rhuav tshem cov hydrocarbon loj loj mus rau hauv cov molecule me me, tseem ceeb hauv kev lag luam roj.
Cov Khoom Siv Hydrocarbon thiab Lawv Cov Kev Ua Haujlwm
Cov chaw tseem ceeb ntawm cov hydrocarbons hauv ntiaj teb yog roj av thiab roj av ntuj. Roj av yog cov khoom sib xyaw ua ke ntawm ntau yam hydrocarbons. Txhawm rau cais thiab siv lawv, kev distillation fractional yog ua nyob rau hauv cov chaw ua roj refineries. Cov khoom ntawm distillation suav nrog:
– LPG
– naphtha
- roj av
- roj av
- roj teeb hnub ci / diesel
- roj lubricating
- paraffin
– asphalt
Txhua feem roj muaj qhov kub thiab siv sib txawv. Ntxiv rau kev distillation, lwm cov txheej txheem xws li reforming, isomerization, thiab cracking siv los txhim kho qhov zoo ntawm roj.
Cov txiaj ntsig ntawm Hydrocarbons hauv lub neej
Cov hydrocarbons muaj lub luag haujlwm tseem ceeb, suav nrog:
1. Cov khoom siv hluav taws xob: roj av, diesel, roj av ntuj, LPG.
2. Cov khoom siv raw rau kev lag luam tshuaj lom neeg: yas, cov xov hluavtaws, cov tshuaj ntxuav tes, cov kuab tshuaj, cov xim, thiab cov tshuaj.
3. Cov khoom siv hauv tsev: paraffin wax, petroleum jelly, roj nplua nyeem.
4. Kev tsim kho vaj tse: asphalt rau kev.
Txawm li cas los xij, kev siv cov hydrocarbons kuj ua rau muaj teeb meem ib puag ncig xws li CO₂ emissions, pa phem, thiab kev pheej hmoo ntawm kev nchuav roj. Yog li ntawd, lub ntiaj teb tam sim no tab tom pib tsim cov zog rov ua dua tshiab thiab cov thev naus laus zis zoo dua rau ib puag ncig.
Xaus
Cov hydrocarbons yog cov sib xyaw ua ke ntawm carbon thiab hydrogen, nrog ntau yam qauv. Hydrocarbons tuaj yeem yog alkanes, alkenes, alkynes, lossis aromatics, txhua tus muaj cov yam ntxwv thiab kev ua haujlwm sib txawv. Lawv ua lub luag haujlwm tseem ceeb hauv kev muab lub zog thiab cov khoom siv raw hauv kev lag luam, tab sis lawv kuj xav tau kev tswj hwm zoo vim lawv qhov cuam tshuam rau ib puag ncig. Los ntawm kev nkag siab txog cov ntsiab lus yooj yim ntawm hydrocarbons, peb tuaj yeem nkag siab zoo dua vim li cas roj, yas, thiab ntau lwm yam khoom niaj hnub no vam khom rau pawg ntawm cov sib xyaw no.
Yog tias koj xav tau, kuv kuj tuaj yeem ua ib qho version ntawm tsab xov xwm no rau cov haujlwm hauv tsev kawm ntawv (yooj yim dua) lossis ib qho version tshawb fawb ntxiv uas ua tiav nrog cov lus nug piv txwv thiab kev sib tham.
