Qhov txawv ntawm Isomers thiab Resonance

2024 Tus sau: Alex Aldridge | [email protected]. Kawg hloov kho: 2023-12-17 13:40

Isomers vs Resonance | Resonance Structures vs Isomers | Txoj Cai Isomers, Stereoisomers, Enantiomers, Diastereomers

Ib lub molecule lossis ion uas muaj tib lub qauv molecular tuaj yeem muaj nyob hauv ntau txoj hauv kev nyob ntawm qhov kev txiav txim sib txuas, tus nqi faib khoom sib txawv, txoj hauv kev uas lawv npaj lawv tus kheej hauv qhov chaw thiab lwm yam.

Isomers

Isomers yog cov sib xyaw sib xyaw nrog tib cov qauv molecular. Muaj ntau hom isomers. Isomers tuaj yeem faib ua ob pawg raws li kev cai lij choj isomers thiab stereoisomers. Constitutional isomers yog isomers qhov twg kev sib txuas ntawm atoms txawv hauv cov molecules. Butane yog qhov yooj yim tshaj plaws alkane los qhia kev cai lij choj isomerism. Butane muaj ob txoj cai isomers, butane nws tus kheej thiab isobutene.

CH₃CH₂CH₂CH₃

Butane Isobutane / 2-methylpropane

Nyob rau hauv stereoisomers atoms txuas nrog tib yam, tsis zoo li kev cai lij choj isomers. Stereoisomers txawv tsuas yog nyob rau hauv kev npaj ntawm lawv cov atoms nyob rau hauv qhov chaw. Stereoisomers tuaj yeem yog ob hom, enantiomers thiab diastereomers. Diastereomers yog cov stereoisomers uas nws cov molecules tsis mirrored dluab ntawm ib leeg. Cis trans isomers ntawm 1, 2-dichloroethene yog diastereomers. Enantiomers yog cov stereoisomers uas nws cov molecules yog cov duab iav tsis pom zoo ntawm ib leeg. Enantiomers tshwm sim tsuas yog nrog chiral molecules. Ib qho chiral molecule yog txhais ua ib qho uas tsis zoo ib yam nrog nws daim iav duab. Yog li ntawd, chiral molecule thiab nws daim iav duab yog enantiomers ntawm ib leeg. Piv txwv li, 2-butanol molecule yog chiral, thiab nws thiab nws daim iav duab yog enantiomers.

Resonance

Thaum sau Lewis cov qauv, peb tsuas yog qhia valence electrons. Los ntawm kev muaj cov atoms sib koom lossis hloov hluav taws xob, peb sim muab txhua lub atom rau cov roj hluav taws xob hluav taws xob zoo. Txawm li cas los xij, ntawm qhov kev sim no, peb tuaj yeem tsim qhov chaw tsim khoom ntawm cov khoom siv hluav taws xob. Yog li ntawd, ntau tshaj ib qho sib npaug Lewis cov qauv tuaj yeem sau rau ntau cov molecules thiab ions. Cov qauv sau los ntawm kev hloov txoj hauj lwm ntawm cov electrons yog hu ua resonance structures. Cov no yog cov qauv uas tsuas muaj nyob hauv txoj kev xav. Tus qauv resonance hais ob qhov tseeb txog cov qauv resonance.

• Tsis muaj ib qho ntawm cov qauv resonance yuav yog tus sawv cev ntawm qhov tseeb molecule; tsis muaj leej twg yuav zoo ib yam li cov tshuaj thiab lub cev ntawm lub cev molecule.
• Qhov tseeb molecule lossis ion yuav zoo tshaj plaws sawv cev los ntawm ib tug hybrid ntawm tag nrho cov resonance qauv.

Cov qauv resonance yog qhia nrog tus xub ↔. Hauv qab no yog cov qauv resonance ntawm carbonate ion (CO₃^2-).

kev tshawb fawb X-ray tau pom tias qhov tseeb molecule nyob nruab nrab ntawm cov resonances. Raws li cov kev tshawb fawb, tag nrho cov carbon-oxygen bonds nyob rau hauv sib npaug zos ntev nyob rau hauv carbonate ion. Txawm li cas los xij, raws li cov qauv saum toj no peb tuaj yeem pom ib qho yog ob daim ntawv cog lus, thiab ob yog ib daim ntawv cog lus. Yog li ntawd, yog tias cov qauv resonance tshwm sim nyias, qhov zoo yuav tsum muaj qhov sib txawv ntawm qhov ntev ntawm cov ion. Tib daim ntawv cog lus ntev qhia tau hais tias tsis muaj ib qho ntawm cov qauv no muaj nyob hauv qhov xwm txheej, es ib qho kev sib xyaw ntawm qhov no tshwm sim.

Qhov txawv ntawm Isomers thiab Resonance yog dab tsi?

• Hauv isomers, atomic arrangement lossis spatial arrangement ntawm cov molecule yuav txawv. Tab sis nyob rau hauv cov qauv resonance, cov yam ntxwv no tsis hloov. Hloov chaw, lawv tsuas muaj qhov hloov pauv ntawm txoj haujlwm ntawm lub tshuab hluav taws xob.

• Isomers yog tam sim no, tab sis cov qauv resonance tsis muaj nyob hauv qhov tseeb. Lawv yog cov qauv kev xav, uas tsuas yog txwv rau txoj kev xav xwb.