有机化学英文课件

OrganicChemistryWilliamH.BrownChristopherS.FooteBrentL.IversonOrganicChemistryWilliamH.BrCovalentBonding&ShapesofMoleculesChapter1

CovalentBonding&ShapesofMOrganicChemistryThestudyofthecompoundsofcarbonOver10millioncompoundshavebeenidentifiedabout1000newonesareidentifiedeachday!Cisasmallatomitformssingle,double,andtriplebondsitisintermediateinelectronegativity(2.5)itformsstrongbondswithC,H,O,N,andsomemetalsOrganicChemistryThestudyofSchematicViewofanAtomasmalldensenucleus,diameter10-14-10-15m,whichcontainspositivelychargedprotonsandmostofthemassoftheatomanextranuclearspace,diameter10-10m,whichcontainsnegativelychargedelectronsSchematicViewofanAtomasmaElectronConfigurationofAtomsElectronsareconfinedtoregionsofspacecalledprincipleenergylevels(shells)eachshellcanhold2n2electrons(n=1,2,3,4......)ElectronConfigurationofAtomElectronConfigurationofAtomsShellsaredividedintosubshellscalledorbitals,whicharedesignatedbytheletterss,p,d,f,........s(onepershell)p(setofthreepershell2andhigher)d(setoffivepershell3andhigher).....ElectronConfigurationofAtomElectronConfigurationofAtomsAufbauPrinciple:

orbitalsfillinorderofincreasingenergyfromlowestenergytohighestenergyPauliExclusionPrinciple:

onlytwoelectronscanoccupyanorbitalandtheirspinsmustbepairedHund’sRule:

whenorbitalsofequalenergyareavailablebuttherearenotenoughelectronstofillallofthem,oneelectronisaddedtoeachorbitalbeforeasecondelectronisaddedtoanyoneofthemElectronConfigurationofAtomElectronConfigurationofAtomsThepairingofelectronspinsElectronConfigurationofAtomElectronConfigurationofAtomsTable1.3TheGround-StateElectronConfigurationofElements1-18ElectronConfigurationofAtomLewisDotStructuresGilbertN.LewisValenceshell:

theoutermostoccupiedelectronshellofanatomValenceelectrons:

electronsinthevalenceshellofanatom;theseelectronsareusedtoformchemicalbondsandinchemicalreactionsLewisdotstructure:

thesymbolofanelementrepresentsthenucleusandallinnershellelectronsdotsrepresentvalenceelectronsLewisDotStructuresGilbertN.LewisDotStructuresTable1.4LewisDotStructuresforElements1-18LewisDotStructuresTable1.4LewisModelofBondingAtomsbondtogethersothateachatomacquiresanelectronconfigurationthesameasthatofthenoblegasnearestitinatomicnumberanatomthatgainselectronsbecomesananionanatomthatloseselectronsbecomesacationtheattractionofanionsandcationsleadstotheformationofionicsolidsanatommayshareelectronswithoneormoreatomstocompleteitsvalenceshell;achemicalbondformedbysharingelectronsiscalledacovalentbondbondsmaybepartiallyionicorpartiallycovalent;thesebondsarecalledpolarcovalentbondsLewisModelofBondingAtomsboElectronegativityElectronegativity:

ameasureofanatom’sattractionfortheelectronsitshareswithanotheratominachemicalbondPaulingscalegenerallyincreaseslefttorightinarowgenerallyincreasesbottomtotopinacolumnElectronegativityElectronegatiFormationofIonsAroughguideline:ionswillformifthedifferenceinelectronegativitybetweeninteractingatomsis1.9orgreaterexample:sodium(EN0.9)andfluorine(EN4.0)weuseasingle-headed(barbed)curvedarrowtoshowthetransferofoneelectronfromNatoFinformingNa+F-,thesingle3selectronfromNaistransferredtothepartiallyfilledvalenceshellofFFormationofIonsAroughguideCovalentBondsThesimplestcovalentbondisthatinH2thesingleelectronsfromeachatomcombinetoformanelectronpairthesharedpairfunctionsintwowayssimultaneously;itissharedbythetwoatomsandfillsthevalenceshellofeachatomThenumberofsharedpairsonesharedpairformsasinglebondtwosharedpairsformadoublebondthreesharedpairsformatriplebondCovalentBondsThesimplestcovPolarandNonpolarCovalentBondsAlthoughallcovalentbondsinvolvesharingofelectrons,theydifferwidelyinthedegreeofsharingWedividecovalentbondsintononpolarcovalentbondspolarcovalentbondsPolarandNonpolarCovalentBoPolarandNonpolarCovalentBondsanexampleofapolarcovalentbondisthatofH-ClthedifferenceinelectronegativitybetweenClandHis3.0-2.1=0.9weshowpolaritybyusingthesymbolsd+andd-,orbyusinganarrowwiththearrowheadpointingtowardthenegativeendandaplussignonthetailofthearrowatthepositiveendPolarandNonpolarCovalentBoPolarCovalentBondsBonddipolemoment(m):

ameasureofthepolarityofacovalentbondtheproductofthechargeoneitheratomofapolarbondtimesthedistancebetweenthenucleiTable1.7showsaveragebonddipolemomentsofselectedcovalentbondsPolarCovalentBondsBonddipolLewisStructuresTowriteaLewisstructuredeterminethenumberofvalenceelectronsdeterminethearrangementofatomsconnecttheatomsbysinglebondsarrangetheremainingelectronssothateachatomhasacompletevalenceshellshowabondingpairofelectronsasasinglelineshowanonbondingpairofelectronsasapairofdotsinasinglebondatomsshareonepairofelectrons,inadoublebondtheysharetwopairsofelectrons,andinatriplebondtheysharethreepairsofelectronsLewisStructuresTowriteaLewLewisStructures-Table1.3Inneutralmoleculeshydrogenhasonebondcarbonhas4bondsandnolonepairsnitrogenhas3bondsand1lonepairoxygenhas2bondsand2lonepairshalogenshave1bondand3lonepairsLewisStructures-Table1.3FormalChargeFormalcharge:thechargeonanatominamoleculeorapolyatomicionToderiveformalcharge1.writeacorrectLewisstructureforthemoleculeorion2.assigneachatomallitsunshared(nonbonding)electronsandone-halfitsshared(bonding)parethisnumberwiththenumberofvalenceelectronsintheneutral,unbondedatomFormalChargeFormalcharge:thFormalChargeExample:

DrawLewisstructures,andshowwhichatomineachbearstheformalchargeFormalChargeExample:DrawLewExceptionstotheOctetRuleMoleculescontainingatomsofGroup3Aelements,particularlyboronandaluminumAluminumchloride:::FBFFClAlClCl6electronsinthevalenceshellsofboronandaluminumBorontrifluoride:::::::::::::::ExceptionstotheOctetRuleMoExceptionstotheOctetRuleAtomsofthird-periodelementshave3dorbitalsandmayexpandtheirvalenceshellstocontainmorethan8electronsphosphorusmayhaveupto10ExceptionstotheOctetRuleAtExceptionstotheOctetRulesulfur,anotherthird-periodelement,formscompoundsinwhichitsvalenceshellcontains8,10,or12electronsExceptionstotheOctetRulesuFunctionalGroupsFunctionalgroup:anatomorgroupofatomswithinamoleculethatshowsacharacteristicsetofphysicalandchemicalpropertiesFunctionalgroupsareimportantforthreereason;theyare1.theunitsbywhichwedivideorganiccompoundsintoclasses2.thesitesofcharacteristicchemicalreactions3.thebasisfornamingorganiccompoundsFunctionalGroupsFunctionalgrAlcoholscontainan-OH(hydroxyl)groupEthanolmayalsobewrittenasacondensedstructuralformulaAlcoholscontainan-OH(hydroxAlcoholsalcoholsareclassifiedasprimary(1°),secondary(2°),ortertiary(3°)dependingonthenumberofcarbonatomsbondedtothecarbonbearingthe-OHgroupAlcoholsalcoholsareclassifieAlcoholstherearetwoalcoholswithmolecularformulaC3H8OAlcoholstherearetwoalcoholsAminescontainanaminogroup;ansp3-hybridizednitrogenbondedtoone,two,orthreecarbonatomsanaminemayby1°,2°,or3°CH3NHHCH3NHCH3CH3NCH3CH3Methylamine(a1°

amine)Dimethylamine(a2°

amine)Trimethylamine(a3°

amine):::Aminescontainanaminogroup;AldehydesandKetonescontainacarbonyl(C=O)groupAldehydesandKetonescontainaCarboxylicAcidscontainacarboxyl(-COOH)groupCarboxylicAcidscontainacarbCarboxylicEstersEster:aderivativeofacarboxylicacidinwhichthecarboxylhydrogenisreplacedbyacarbongroupCarboxylicEstersEster:aderiCarboxylicAmideCarboxylicamide,commonlyreferredtoasanamide:aderivativeofacarboxylicacidinwhichthe-OHofthe-COOHgroupisreplacedbyanaminethesixatomsoftheamidefunctionalgrouplieinaplanewithbondanglesofapproximately120°CarboxylicAmideCarboxylicamiVSEPRBasedonthetwinconceptsthatatomsaresurroundedbyregionsofelectrondensityregionsofelectrondensityrepeleachotherVSEPRBasedonthetwinconceptVSEPRModelExample:

predictallbondanglesforthesemoleculesandionsVSEPRModelExample:predictalPolarandNonpolarMoleculesTodetermineifamoleculeispolar,weneedtodetermineifthemoleculehaspolarbondsthearrangementofthesebondsinspaceMoleculardipolemoment():thevectorsumoftheindividualbonddipolemomentsinamoleculereportedindebyes(D)PolarandNonpolarMoleculesToPolarandNonpolarMoleculesthesemoleculeshavepolarbonds,buteachhasazerodipolemomentPolarandNonpolarMoleculesthPolarandNonpolarMoleculesthesemoleculeshavepolarbondsandarepolarmoleculesPolarandNonpolarMoleculesthPolarandNonpolarMoleculesformaldehydehaspolarbondsandisapolarmoleculePolarandNonpolarMoleculesfoResonanceFormanymoleculesandions,nosingleLewisstructureprovidesatrulyaccuraterepresentationResonanceFormanymoleculesanResonanceLinusPauling-1930smanymoleculesandionsarebestdescribedbywritingtwoormoreLewisstructuresindividualLewisstructuresarecalledcontributingstructuresconnectindividualcontributingstructuresbydouble-headed(resonance)arrowsthemoleculeorionisahybridofthevariouscontributingstructuresResonanceLinusPauling-1930sResonanceExamples:

equivalentcontributingstructuresResonanceExamples:equivalentResonanceCurvedarrow:

asymbolusedtoshowtheredistributionofvalenceelectronsInusingcurvedarrows,thereareonlytwoallowedtypesofelectronredistribution:fromabondtoanadjacentatomfromanatomtoanadjacentbondElectronpushingisasurvivalskillinorganicchemistrylearnitwell!ResonanceCurvedarrow:asymboResonanceAllcontributingstructuresmust1.havethesamenumberofvalenceelectrons2.obeytherulesofcovalentbondingnomorethan2electronsinthevalenceshellofHnomorethan8electronsinthevalenceshellofa2ndperiodelement3rdperiodelements,suchasPandS,mayhaveupto12electronsintheirvalenceshells3.differonlyindistributionofvalenceelectrons;thepositionofallnucleimustbethesame4.havethesamenumberofpairedandunpairedelectronsResonanceAllcontributingstruResonanceThecarbonateion,forexampleahybridofthreeequivalentcontributingstructuresthenegativechargeisdistributedequallyamongthethreeoxygensResonanceThecarbonateion,foResonancePreference1:filledvalenceshellsstructuresinwhichallatomshavefilledvalenceshellscontributemorethanthosewithoneormoreunfilledvalenceshells••••••Greatercontribution;bothcarbonandoxygenhavecompletevalenceshellsLessercontribution;carbonhasonly6electronsinitsvalenceshell++CCH3OCH3OHHCHHResonancePreference1:filledResonancePreference2:maximumnumberofcovalentbondsstructureswithagreaternumberofcovalentbondscontributemorethanthosewithfewercovalentbondsResonancePreference2:maximumResonancePreference3:leastseparationofunlikechargestructureswithseparationofunlikechargescontributelessthanthosewithnochargeseparationLessercontribution(separationofunlikecharges)CH3-C-CH3CH3-C-CH3Greatercontribution(noseparationofunlikecharges)O

-O:::::ResonancePreference3:leastsResonancePreference4:negativechargeonthemoreelectronegativeatomstructuresthatcarryanegativechargeonthemoreelectronegativeatomcontributemorethanthosewiththenegativechargeonthelesselectronegativeatomResonancePreference4:negativQuantumorWaveMechanicsAlbertEinstein:E=hn(energyisquantized)lighthasparticlepropertiesLouisdeBroglie:wave/particledualityErwinSchrödinger:waveequationwavefunction,:asolutiontoasetofequationsthatdepictstheenergyofanelectroninanatomeachwavefunctionisassociatedwithauniquesetofquantumnumberseachwavefunctionoccupiesthree-dimensionalspaceandiscalledanorbital

2istheprobabilityoffindinganelectronatagivenpointinspaceQuantumorWaveMechanicsAlberShapesof1sand2sOrbitalsProbabilitydistribution(2)for1sand2sorbitalsshowinganarbitraryboundarysurfacecontainingabout95%oftheelectrondensityShapesof1sand2sOrbitalsPrShapesofaSetof2pAtomicOrbitalsThree-dimensionalshapesof2patomicorbitalsShapesofaSetof2pAtomicOMolecularOrbitalTheoryElectronsinatomsexistinatomicorbitalsElectronsinmoleculesexistinmolecularorbitals(MOs)UsingtheSchrödingerequation,wecancalculatetheshapesandenergiesofMOsMolecularOrbitalTheoryElectrMolecularOrbitalTheoryRules:combinationofnatomicorbitals(mathematicallyaddingandsubtractingwavefunctions)givesnMOs(newwavefunctions)MOsarearrangedinorderofincreasingenergyMOfillingisgovernedbythesamerulesasforatomicorbitals:Aufbauprinciple:fillbeginningwithLUMOPauliexclusionprinciple:nomorethan2e-inaMOHund’srule:whentwoormoreMOsofequivalentenergyareavailable,add1e-toeachbeforefillinganyoneofthemwith2e-MolecularOrbitalTheoryRules:MolecularOrbitalTheoryTerminologygroundstate=lowestenergystateexcitedstate=NOTlowestenergystate

=sigmabondingMO

*=sigmaantibondingMO

=pibondingMO

*=piantibondingMOHOMO=highestoccupiedMOLUMO=lowestunoccupiedMOMolecularOrbitalTheoryTerminMolecularOrbitalTheorySigma1sbondingandantibondingMOsMolecularOrbitalTheorySigmaMolecularOrbitalTheoryMOenergydiagramforH2:(a)groundstateand(b)lowestexcitedstateMolecularOrbitalTheoryMOeneMolecularOrbitalscomputedsigmabondingandantibondingMOsforH2MolecularOrbitalscomputedsigMolecularOrbitalspibondingandantibondingMOsMolecularOrbitalspibondingaMolecularOrbitalscomputedpibondingandantibondingMOsforethyleneMolecularOrbitalscomputedpiMolecularOrbitalscomputedpibondingandantibondingorbitalsforformaldehydeMolecularOrbitalscomputedpiHybridOrbitalsTheProblem:bondingby2sand2patomicorbitalswouldgivebondanglesofapproximately90°insteadweobservebondanglesofapproximately109.5°,120°,and180°ASolutionhybridizationofatomicorbitals2ndrowelementsusesp3,sp2,andsphybridorbitalsforbondingHybridOrbitalsTheProblem:HybridOrbitalsHybridizationoforbitals(L.Pauling)thecombinationoftwoormoreatomicorbitalsformsanewsetofatomicorbitals,calledhybridorbitalsWedealwiththreetypesofhybridorbitalssp3

(onesorbital+threeporbitals)sp2

(onesorbital+twoporbitals)sp(onesorbital+oneporbital)Overlapofhybridorbitalscanformtwotypesofbondsdependingonthegeometryofoverlapbonds

areformedby“direct”overlapbonds

areformedby“parallel”overlapHybridOrbitalsHybridizationosp3HybridOrbitalseachsp3hybridorbitalhastwolobesofunequalsizethesignofthewavefunctionispositiveinonelobe,negativeintheother,andzeroatthenucleusthefoursp3hybridorbitalsaredirectedtowardthecornersofaregulartetrahedronatanglesof109.5°sp3HybridOrbitalseachsp3hysp3HybridOrbitalsorbitaloverlappicturesofmethane,ammonia,andwatersp3HybridOrbitalsorbitalovesp2HybridOrbitalstheaxesofthethreesp2hybridorbitalslieinaplaneandaredirectedtowardthecornersofanequilateraltriangletheunhybridized2porbitalliesperpendiculartotheplaneofthethreehybridorbitalssp2HybridOrbitalstheaxesofBondinginEthyleneBondinginEthyleneBondinginFormaldehydeBondinginFormaldehydespHybridOrbitalstwolobesofunequalsizeatanangleof180°theunhybridized2porbitalsareperpendiculartoeachotherandtothelinecreatedbytheaxesofthetwosphybridorbitalsspHybridOrbitalstwolobesofBondinginAcetylene,C2H2BondinginAcetylene,C2H2HybridOrbitalsHybridOrbitalsBondLengthsandBondStrengthsBondLengthsandBondStrengthCovalentBonds&ShapesofMoleculesEndChapter1CovalentBonds&ShapesofMolOrganicChemistryWilliamH.BrownChristopherS.FooteBrentL.IversonOrganicChemistryWilliamH.BrCovalentBonding&ShapesofMoleculesChapter1

CovalentBonding&ShapesofMOrganicChemistryThestudyofthecompoundsofcarbonOver10millioncompoundshavebeenidentifiedabout1000newonesareidentifiedeachday!Cisasmallatomitformssingle,double,andtriplebondsitisintermediateinelectronegativity(2.5)itformsstrongbondswithC,H,O,N,andsomemetalsOrganicChemistryThestudyofSchematicViewofanAtomasmalldensenucleus,diameter10-14-10-15m,whichcontainspositivelychargedprotonsandmostofthemassoftheatomanextranuclearspace,diameter10-10m,whichcontainsnegativelychargedelectronsSchematicViewofanAtomasmaElectronConfigurationofAtomsElectronsareconfinedtoregionsofspacecalledprincipleenergylevels(shells)eachshellcanhold2n2electrons(n=1,2,3,4......)ElectronConfigurationofAtomElectronConfigurationofAtomsShellsaredividedintosubshellscalledorbitals,whicharedesignatedbytheletterss,p,d,f,........s(onepershell)p(setofthreepershell2andhigher)d(setoffivepershell3andhigher).....ElectronConfigurationofAtomElectronConfigurationofAtomsAufbauPrinciple:

orbitalsfillinorderofincreasingenergyfromlowestenergytohighestenergyPauliExclusionPrinciple:

onlytwoelectronscanoccupyanorbitalandtheirspinsmustbepairedHund’sRule:

whenorbitalsofequalenergyareavailablebuttherearenotenoughelectronstofillallofthem,oneelectronisaddedtoeachorbitalbeforeasecondelectronisaddedtoanyoneofthemElectronConfigurationofAtomElectronConfigurationofAtomsThepairingofelectronspinsElectronConfigurationofAtomElectronConfigurationofAtomsTable1.3TheGround-StateElectronConfigurationofElements1-18ElectronConfigurationofAtomLewisDotStructuresGilbertN.LewisValenceshell:

theoutermostoccupiedelectronshellofanatomValenceelectrons:

electronsinthevalenceshellofanatom;theseelectronsareusedtoformchemicalbondsandinchemicalreactionsLewisdotstructure:

thesymbolofanelementrepresentsthenucleusandallinnershellelectronsdotsrepresentvalenceelectronsLewisDotStructuresGilbertN.LewisDotStructuresTable1.4LewisDotStructuresforElements1-18LewisDotStructuresTable1.4LewisModelofBondingAtomsbondtogethersothateachatomacquiresanelectronconfigurationthesameasthatofthenoblegasnearestitinatomicnumberanatomthatgainselectronsbecomesananionanatomthatloseselectronsbecomesacationtheattractionofanionsandcationsleadstotheformationofionicsolidsanatommayshareelectronswithoneormoreatomstocompleteitsvalenceshell;achemicalbondformedbysharingelectronsiscalledacovalentbondbondsmaybepartiallyionicorpartiallycovalent;thesebondsarecalledpolarcovalentbondsLewisModelofBondingAtomsboElectronegativityElectronegativity:

ameasureofanatom’sattractionfortheelectronsitshareswithanotheratominachemicalbondPaulingscalegenerallyincreaseslefttorightinarowgenerallyincreasesbottomtotopinacolumnElectronegativityElectronegatiFormationofIonsAroughguideline:ionswillformifthedifferenceinelectronegativitybetweeninteractingatomsis1.9orgreaterexample:sodium(EN0.9)andfluorine(EN4.0)weuseasingle-headed(barbed)curvedarrowtoshowthetransferofoneelectronfromNatoFinformingNa+F-,thesingle3selectronfromNaistransferredtothepartiallyfilledvalenceshellofFFormationofIonsAroughguideCovalentBondsThesimplestcovalentbondisthatinH2thesingleelectronsfromeachatomcombinetoformanelectronpairthesharedpairfunctionsintwowayssimultaneously;itissharedbythetwoatomsandfillsthevalenceshellofeachatomThenumberofsharedpairsonesharedpairformsasinglebondtwosharedpairsformadoublebondthreesharedpairsformatriplebondCovalentBondsThesimplestcovPolarandNonpolarCovalentBondsAlthoughallcovalentbondsinvolvesharingofelectrons,theydifferwidelyinthedegreeofsharingWedividecovalentbondsintononpolarcovalentbondspolarcovalentbondsPolarandNonpolarCovalentBoPolarandNonpolarCovalentBondsanexampleofapolarcovalentbondisthatofH-ClthedifferenceinelectronegativitybetweenClandHis3.0-2.1=0.9weshowpolaritybyusingthesymbolsd+andd-,orbyusinganarrowwiththearrowheadpointingtowardthenegativeendandaplussignonthetailofthearrowatthepositiveendPolarandNonpolarCovalentBoPolarCovalentBondsBonddipolemoment(m):

ameasureofthepolarityofacovalentbondtheproductofthechargeoneitheratomofapolarbondtimesthedistancebetweenthenucleiTable1.7showsaveragebonddipolemomentsofselectedcovalentbondsPolarCovalentBondsBonddipolLewisStructuresTowriteaLewisstructuredeterminethenumberofvalenceelectronsdeterminethearrangementofatomsconnecttheatomsbysinglebondsarrangetheremainingelectronssothateachatomhasacompletevalenceshellshowabondingpairofelectronsasasinglelineshowanonbondingpairofelectronsasapairofdotsinasinglebondatomsshareonepairofelectrons,inadoublebondtheysharetwopairsofelectrons,andinatriplebondtheysharethreepairsofelectronsLewisStructuresTowriteaLewLewisStructures-Table1.3Inneutralmoleculeshydrogenhasonebondcarbonhas4bondsandnolonepairsnitrogenhas3bondsand1lonepairoxygenhas2bondsand2lonepairshalogenshave1bondand3lonepairsLewisStructures-Table1.3FormalChargeFormalcharge:thechargeonanatominamoleculeorapolyatomicionToderiveformalcharge1.writeacorrectLewisstructureforthemoleculeorion2.assigneachatomallitsunshared(nonbonding)electronsandone-halfitsshared(bonding)parethisnumberwiththenumberofvalenceelectronsintheneutral,unbondedatomFormalChargeFormalcharge:thFormalChargeExample:

DrawLewisstructures,andshowwhichatomineachbearstheformalchargeFormalChargeExample:DrawLewExceptionstotheOctetRuleMoleculescontainingatomsofGroup3Aelements,particularlyboronandaluminumAluminumchloride:::FBFFClAlClCl6electronsinthevalenceshellsofboronandaluminumBorontrifluoride:::::::::::::::ExceptionstotheOctetRuleMoExceptionstotheOctetRuleAtomsofthird-periodelementshave3dorbitalsandmayexpandtheirvalenceshellstocontainmorethan8electronsphosphorusmayhaveupto10ExceptionstotheOctetRuleAtExceptionstotheOctetRulesulfur,anotherthird-periodelement,formscompoundsinwhichitsvalenceshellcontains8,10,or12electronsExceptionstotheOctetRulesuFunctionalGroupsFunctionalgroup:anatomorgroupofatomswithinamoleculethatshowsacharacteristicsetofphysicalandchemicalpropertiesFunctionalgroupsareimportantforthreereason;theyare1.theunitsbywhichwedivideorganiccompoundsintoclasses2.thesitesofcharacteristicchemicalreactions3.thebasisfornamingorganiccompoundsFunctionalGroupsFunctionalgrAlcoholscontainan-OH(hydroxyl)groupEthanolmayalsobewrittenasacondensedstructuralformulaAlcoholscontainan-OH(hydroxAlcoholsalcoholsareclassifiedasprimary(1°),secondary(2°),ortertiary(3°)dependingonthenumberofcarbonatomsbondedtothecarbonbearingthe-OHgroupAlcoholsalcoholsareclassifieAlcoholstherearetwoalcoholswithmolecularformulaC3H8OAlcoholstherearetwoalcoholsAminescontainanaminogroup;ansp3-hybridizednitrogenbondedtoone,two,orthreecarbonatomsanaminemayby1°,2°,or3°CH3NHHCH3NHCH3CH3NCH3CH3Methylamine(a1°

amine)Dimethylamine(a2°

amine)Trimethylamine(a3°

amine):::Aminescontainanaminogroup;AldehydesandKetonescontainacarbonyl(C=O)groupAldehydesandKetonescontainaCarboxylicAcidscontainacarboxyl(-COOH)groupCarboxylicAcidscontainacarbCarboxylicEstersEster:aderivativeofacarboxylicacidinwhichthecarboxylhydrogenisreplacedbyacarbongroupCarboxylicEstersEster:aderiCarboxylicAmideCarboxylicamide,commonlyreferredtoasanamide:aderivativeofacarboxylicacidinwhichthe-OHofthe-COOHgroupisreplacedbyanaminethesixatomsoftheamidefunctionalgrouplieinaplanewithbondanglesofapproximately120°CarboxylicAmideCarboxylicamiVSEPRBasedonthetwinconceptsthatatomsaresurroundedbyregionsofelectrondensityregionsofelectrondensityrepeleachotherVSEPRBasedonthetwinconceptVSEPRModelExample:

predictallbondanglesforthesemoleculesandionsVSEPRModelExample:predictalPolarandNonpolarMoleculesTodetermineifamoleculeispolar,weneedtodetermineifthemoleculehaspolarbondsthearrangementofthesebondsinspaceMoleculardipolemoment():thevectorsumoftheindividualbonddipolemomentsinamoleculereportedindebyes(D)PolarandNonpolarMoleculesToPolarandNonpolarMoleculesthesemoleculeshavepolarbonds,buteachhasazerodipolemomentPolarandNonpolarMoleculesthPolarandNonpolarMoleculesthesemoleculeshavepolarbondsandarepolarmoleculesPolarandNonpol