Gịnị bụ ihe atụ Jeremaya mere maka alkanes

Onye ọ bụla na klas nke chemical ogige pụrụ igosipụta Njirimara ruru ha electronic Ọdịdị. N'ihi alkanes typical nnọchi mmeghachi omume, cleavage ma ọ bụ molekụla ọxịdashọn. All chemical Filiks nwere onwe ha akpan akpan eruba, nke ga-n'ihu atụle.

Gịnị bụ alkanes

Nke a jupụta hydrocarbon ogige, nke na-mara dị ka paraffin. Ndị a na ụmụ irighiri iso nke naanị carbon na hydrogen atọm, bụ n'usoro ma ọ bụ branched acyclic agbụ ígwè nke na e nwere nanị otu compound. Nyere àgwà nke klas, ị nwere ike gbakọọ ihe mmeghachi omume e ji mara nke alkanes. Ha na-erube isi nke usoro maka dum klas: H _{2n + 2} C _n.

chemical Ọdịdị

Paraffin molekul mejupụtara carbon atọm egosi sp ³ hybridization. Ha niile anọ valence orbitals nwere otu udi, ike na direction na ohere. The size nke n'akuku n'etiti ike na ọkwa nke 109 ° na 28 '.

Ọnụnọ nke otu nkekọ na ụmụ irighiri na-ekpebi ihe ndị Jeremaya mere, bụ ihe e ji mara nke alkanes. Ha na-ebu σ-compound. Nkwurịta okwu n'etiti carbons bụ nonpolar na weakly polarizable, ọ bụ ubé ogologo oge karịa C-H. Ọzọkwa, elektrọn njupụta nke a na-agbanwe gaa a carbon atọm bụ ihe kasị electronegative. Ihe compound e ji C-H ala polarity.

nnọchi mmeghachi omume

Bekee klas paraffins nwere a ala chemical ọrụ. Nke a nwere ike kọwara site n'ike nke nkekọ dị n'etiti C-C na C-H, nke bụ ike na-agbaji n'ihi nke na-abụghị polarity. The ndabere nke ha mbibi homolytic usoro, agaghi asu free buu ụdị aka. Ọ bụ ya mere alkanes na-ji a nnọchi mmeghachi omume. Dị otú ahụ bekee na-enwe ike na-emekọ ihe ndị mmiri na ụmụ irighiri ihe ma ọ bụ ion nke ihe-ndebe-ebu.

Ha ọkwá free buu nnọchi nke hydrogen atọm na-dochie anya halogen ọcha ma ọ bụ ndị ọzọ nọ n'ọrụ otu. Mmeghachi omume ndị a na-agụnye usoro metụtara halogenation, sulfochlorination na nitration. Ndị a na-eduga nkwadebe nke alkane emepụta. Kpatara nnọchi Jeremaya mere site na a free buu usoro bụ isi ụdị atọ nkebi:

1. Usoro na-amalite na a nucleation nnabata ma ọ bụ ogologo, nke free radicals na-guzobere. The akpali bụ isi mmalite nke ultraviolet ìhè na kpo oku.
2. Mgbe ahụ amalite agbụ ígwè nke soje ifịk ahụ rụrụ mmekọrịta-adịghị ejekwa ozi na ụmụ irighiri ihe. Bụ ha cheghariri n'ime ụmụ irighiri na radicals, karị.
3. The ikpeazụ nzọụkwụ ga-agbaji yinye. E recombination ma ọ bụ ofufe nke nọ n'ọrụ ahụ. N'ihi ya kwụsị mmepe nke a yinye mmeghachi omume.

The usoro nke halogenation

Ọ dabeere na usoro nke buu ụdị. Alkane halogenation mmeghachi omume na-ewe ebe site irradiation na ultraviolet ìhè na kpo oku nke a ngwakọta nke halogens na hydrocarbons.

All nkebi nke usoro bụ isiokwu ndị na-achị na kwuru Markovnikov. Ọ na-ekwu na dabara nnọchi site halogen, karịsịa hydrogen, nke bụ nke ndị hydrogenated carbon. Halogenation-ewe ebe na-eso usoro: si a bụ isi ka a tertiary carbon atọm.

The usoro na-ewe ebe mma na alkane ụmụ irighiri na ogologo isi hydrocarbon yinye. Nke a bụ n'ihi na ọnụ nke ionizing ike na a direction, umi mfe rapara elektrọn.

Otu ihe atụ bụ chlorination nke methane ụmụ irighiri. Akparamagwa nke ultraviolet radieshon na-akpata a gbawara chlorine buu umu na mepụta ihe agha na alkane. Nkewa emee na guzobe atọm hydrogen H ₃ C · ma ọ bụ a methyl buu. Ndị dị otú ahụ a urughuru, n'aka nke ya, na-awakpo ndị molekụla chlorine, na-eduga mbibi nke ya Ọdịdị na guzobere ọhụrụ chemical.

Mgbe ọ bụla ogbo nnọchi usoro a rụrụ naanị otu hydrogen atọm. The halogenation mmeghachi omume nke alkanes na-eduga ná gradual guzobere hlormetanovoy, dichloromethane, na trihlormetanovoy tetrahlormetanovoy molekul.

Schematically, usoro bụ dị ka ndị:

H ₄ C + cl: cl → H ₃ CCl + HCl,

H ₃ CCl + cl: cl → H ₂ CCl ₂ + HCl,

H ₂ CCl ₂ + cl: cl → HCCl ₃ + HCl,

HCCl ₃ + cl: cl → CCl ₄ + HCl.

N'ụzọ dị iche na chlorination nke methane ụmụ irighiri na-ebu ndị dị otú ahụ a usoro na ndị ọzọ alkanes ji nweta bekee enwe hydrogen nnọchi abụghị onye carbon atọm, na a ole na ole. Ha quantitative ruru metụtara na okpomọkụ egosi. Na oyi ọnọdụ, a ọnụ ke ọnụego nke guzobere nkwekọrịta na tertiary, sekọndrị na isi Ọdịdị.

Na-amụba okpomọkụ iche ọsọ nke guzobere ndị dị otú ahụ ogige bụ boo. Na halogenation usoro e nwere mmetụta nke static akpata nke na-egosi a dị iche iche gbasara nke puru omume nkukota nke buu na carbon atọm.

Usoro halogenation na ayodiin adịghị ime n'okpuru nkịtị ọnọdụ. Ọ dị mkpa ka ike pụrụ iche ọnọdụ. Mgbe ọ gụrụ methane emee dika halogen omume hydrogen iodide. Ọ nwere mmetụta methyl iodide dị ka a N'ihi kwụpụta mbụ reactants methane na ayodiin. Ndị dị otú ahụ a mmeghachi omume a na-atụle ga-reversible.

Wurtz mmeghachi omume nke alkanes

Ọ bụ a na usoro maka inweta hydrocarbons na jupụta symmetrical Ọdịdị. Dị ka reactants na-eji sodium metal, alkyl bromides ma ọ bụ alkyl chlorides. Na ha na mmekọrịta kwadebere sodium halide na ụba hydrocarbon yinye nke bụ nchikota nke abụọ hydrocarbon radicals. Schematically, na njikọ dị ka ndị a: R-cl + cl-R + 2Na → R-R + 2NaCl.

Wurtz mmeghachi omume nke alkanes bụ nanị kwe omume ma ọ bụrụ na ndị halogens na ha na ụmụ irighiri na-isi carbon atọm. E.g., Kra ₃ -CH ₂ -CH ₂ br.

Ọ bụrụ na n'oge play nke galogenuglevodorododnaya ngwakọta abụọ ogige, na odide nke atọ dị iche iche na nkpọrọ kpụrụ ngwaahịa. Otu ihe atụ nke a bụ mmeghachi omume nwere ike ije ozi dị ka sodium alkane mmekọrịta chloromethanes na hloretanom. The mmepụta bụ a ngwakọta gụnyere butane, propane ma ethane.

E wezụga sodium, omume na-eji ndị ọzọ alkali ọla, nke na-agụnye lithium ma ọ bụ potassium.

usoro sulfochlorination

Ọ na-akpọ ndị Reed mmeghachi omume. Ọ na-agba na ụkpụrụ nke free ndochi. Nke a na ụdị mmeghachi omume a na-ahụkarị nke alkanes ka ihe nke a ngwakọta nke sọlfọ dioxide na molekụla chlorine na ọnụnọ nke ultraviolet radieshon.

The usoro-amalite na nnabata nke yinye usoro, agaghi asu chlorine enwetara site na abụọ radicals. Otu agha alkane nke na-enye ịrị elu na alkyl ahụ na ụmụ irighiri nke hydrogen chloride. Site hydrocarbon buu mmasị na-etolite sọlfọ dioxide mgbagwoju ahụ. Iji akawanye kpọọ emee otu chlorine atọm si ọzọ molekul. The ikpeazụ ihe onwunwe bụ ihe alkane sulfonyl chloride, ọ na-eji na njikọ nke elu-n'ọrụ ogige.

Schematically, usoro anya dị ka nke a:

CLCL → ^hv ∙ cl + ∙ cl,

Ọrụ Nchịkwa + ∙ cl → R ∙ + HCl,

R ∙ + OSO → ∙ RSO _2,

∙ RSO ₂ + ClCl → RSO ₂ cl + ∙ cl.

The Filiks metụtara na nitration

Alkanes eme na nitric acid na a ngwọta 10% na na tetravalent nitrogen oxide na a gaseous ala. Ọnọdụ nke ya omume dị elu ụkpụrụ nke okpomọkụ (banyere 140 ° C) na ala nsogbu ụkpụrụ. Na mmepụta emepụta nitroalkanes.

The usoro nke free-buu ụdị aha mgbe ọkà mmụta sayensị Konovalov, meghere nitration njikọ: Kra ₄ + HNO ₃ → Kra ₃ NO ₂ + H ₂ O.

The usoro nke cleavage

N'ihi na-ahụkarị alkane dehydrogenation na cracking. Methane molekul dabara a zuru thermal decomposition.

Ihe bụ isi usoro nke n'elu Jeremaya mere bụ cleavage nke atọm si alkanes.

dehydrogenation usoro

Mgbe kewara ndị hydrogen atọm na carbon ọkpọ paraffins, ma e wezụga methane na-nwetara unsaturated ogige. Dị otú ahụ chemical Jeremaya mere, nke alkanes nwalere na elu okpomọkụ (400 600 ° C) na n'okpuru edinam accelerators ka platinum, nickel, chromium oxides na aluminum.

Ọ bụrụ na-ekere òkè na mmeghachi omume nke ethane ma ọ bụ propane ụmụ irighiri, mgbe ahụ, ya na ngwaahịa ga-ethene ma ọ bụ propene na otu abụọ nkekọ.

The dehydrogenation nke anọ ma ọ bụ ise-carbon ọkpụkpụ nwetara diene compound. Si kpụrụ butane-1,3 butadiene na 1,2-butadiene.

Ọ bụrụ na ugbu a na mmeghachi omume bekee na-6 ma ọ bụ karịa carbon atọm, na benzene a kpụrụ. Ọ nwere ihe aromatic mgbaaka na atọ abụọ agbụ.

The usoro metụtara na decomposition

N'okpuru elu okpomọkụ mmeghachi omume nke alkanes nwere ike gafee na a ọdịiche carbon agbụ na guzobere nke nọ n'ọrụ na umu nke buu ụdị. Ndị dị otú ahụ Filiks na-ezo dị ka cracking ma ọ bụ pyrolysis.

Kpo oku reactants ka okpomọkụ uku 500 ° C, na-arụpụta na decomposition nke ụmụ irighiri na nke na-guzobere mgbagwoju mixtures nke alkyl-ụdị radicals.

-Arụ n'okpuru ike kpo oku nke pyrolysis nke alkanes na a carbon yinye ogologo ruru nweta jupụta na unsaturated ogige. Ọ na-akpọ thermal cracking. Usoro a na-eji ruo n'etiti narị afọ nke 20.

The drawback bụ iji nweta hydrocarbons na a ala octane nọmba (erughị 65), n'ihi ya, e dochie cracking mkpali. The usoro na-ewe ke okpomọkụ na-n'okpuru 440 ° C, na nrụgide nke na-erughị 15 atmospheres, na ọnụnọ nke ihe aluminosilicate ome osooso ntọhapụ alkanes enwe a branched Ọdịdị. Otu ihe atụ bụ pyrolysis nke methane: 2 Ihe E Mere ₄ → ^{t °} C ₂ H ₂ + 3H _2. The kpụrụ acetylene na molekụla hydrogen n'oge mmeghachi omume.

The molekul nwere ike doro methane akakabarede. A mmeghachi omume na-achọ mmiri ma a nickel mkpali. The mmepụta bụ a ngwakọta nke carbon monoxide na hydrogen.

ọxịdashọn Filiks

The chemical mmeghachi omume na-ahụkarị alkane jikọtara elektrọn mmetụta.

E auto-ọxịdashọn nke paraffins. Ọ na-agụnye a free buu usoro nke ọxịdashọn nke jupụta hydrocarbons. N'oge mmeghachi omume, mmiri mmiri na-adọ alkane hydroperoxide nwetara. Ná mmalite paraffin molekul mkpatụ na oxygen na ekenyela ifịk radicals. Ọzọ, alkyl urughuru interacts ọzọ molekul O _2, enwetara ∙ Roo. Ebe ọ bụ na peroxy buu nke a ọdụdụ acid na-kpọtụụrụ alkane molekul, na mgbe ahụ wepụtara hydroperoxide. Otu ihe atụ bụ autooxidation nke ethane:

C ₂ H ₆ + O ₂ → ∙ C ₂ H ₅ + HOO ∙,

∙ C ₅ H ₂ + O ₂ → ∙ OOC ₂ H _5,

∙ OOC ₂ H ₅ + C ₂ H ₆ → HOOC ₂ H ₅ + ∙ C ₂ H _5.

N'ihi alkane ji mmeghachi omume nke combustion na ndị tumadi chemical Njirimara, na-ekpebi ihe ndị mejupụtara nke a mmanụ ụgbọala. Ha na-oxidative na ọdịdị na emission nke okpomọkụ: 2C ₂ H ₆ + 7O ₂ → 4CO ₂ + 6H ₂ O.

Ọ bụrụ na usoro a hụrụ na a obere ego nke oxygen, ọgwụgwụ ngwaahịa nwere ike ịbụ a divalent carbon ma ọ bụ carbon monoxide, nke a kpebisiri ike site ịta nke O _2.

Na ọxịdashọn nke alkanes n'okpuru nduzi nke catalytic bekee na kpụ ọkụ n'ọnụ na 200 ° C na-nwetara mmanya molekul, aldehyde ma ọ bụ carboxylic acid.

GOSIRI ethane:

C ₂ H ₆ + O ₂ → C ₂ H ₅ OH (ethanol),

C ₂ H ₆ + O ₂ → Kra ₃ Cho + H ₂ O (ethanal na mmiri)

2C ₂ H ₆ + 3o ₂ → 2 Ihe E Mere ₃ COOH + 2H ₂ O (ethanoic acid na mmiri).

Alkanes nwere ike oxidized n'okpuru edinam nke cyclic peroxides trinomial. Ndị a gụnyere dimethyl dioxirane. N'ihi bụ ọxịdashọn nke paraffins mmanya molekul.

Representatives paraffins adịghị eme ka KMnO ₄ ma ọ bụ potassium permanganate, nakwa dị ka bromine mmiri.

isomerization

On alkanes ji nnọchi ụdị mmeghachi omume na-electrophilic usoro. Nke a na-ezo isomerization nke carbon yinye. Catalyzes usoro a na aluminum chloride, nke na-meghachi omume na a jupụta paraffin. Otu ihe atụ bụ isomerization nke butane molekul, nke bụ 2-methylpropane: C ₄ H ₁₀ → C ₃ H ₇ Kra _3.

usoro ekpomeekpo

Jupụta bekee na nke isi carbon yinye nwere isii ma ọ bụ karịa carbon atọm, ike nke na-eduzi dehydrocyclization. Maka obere ụmụ irighiri na-adịghị ihe e ji mara nke a mmeghachi omume. N'ihi bụ mgbe a isii membered mgbanaka ka cyclohexane na nkwekọrịta-ya nile.

Na ọnụnọ nke mmeghachi omume accelerators, na-aga n'ihu dehydrogenation nke akakabarede n'ime a ọzọ mụ benzene mgbanaka. Ọ na-adị n'ịtụgharị acyclic hydrocarbons na aromatics ma ọ bụ arena. Otu ihe atụ bụ dehydrocyclization nke hexane:

H ₃ C-Kra ₂ - Kra ₂ - Kra ₂ - Kra ₂ -CH ₃ → C ₆ H ₁₂ (cyclohexane)

C ₆ H ₁₂ → C ₆ H ₆ + 3H ₂ (benzene).