Organic Chemistry Notes

chapter1 generalchemistryreview

diapolemoment

representation
ofapartialchargedistribution in a polarcovalentbondasarrows
arrowspointtowards negative
charge
thenetdiapoleofthemoleculedeterminesthepolarity
example

some sdue
zerodiapole nonpolar
netdiapolemoment symmetrynetdiapolemay

bezero nonpolar C symmetry

I
c i
g
electronegativity

toattractelectrons
electronegativitytendency

periodictable F C3r SC



Chemical
bonding

nonpolar 0.5

polar0.5 1.7
ionic 1.7

formalcharge


formalcharge ofvalenceelectrons oflonepairelectrons1121 bondingelectrons

themoleculeandnegativeformalchargesaremorestableon
formalchargeswilladduptothetotalchargeof

themostelectronegativeatom

,constitutionalisomers

thesame
connectedbuthave
constitutional structuralisomersdifferintheorderinwhichtheatomsare

molecularformula

examples
ethanol dimethylether



cc C c
hydrogenbond greaterpolarity

greaterboilingpoint OHbonds

of tobreak
requirealot energy notethismoleculeispolar



C C3
bentstructure

xample2

eachintermediatecarbonbonds
totwohydrogen
ytwoterminalcarbons
Cl
Cl onlybondedtoonehydrogen
asitcanonlymakedbonds
a aterminalcarbonwill
havethreehydrogenbonds molecularformula cectlaCHICH.la

eachpeakrepresentsacarbon


molecular
formula Cahall

,hybridization

typesofhybridorbitals

splinear 2 bonds 1800bondangle
spatrigonalplanar 3bonds 1200bondangle

sp3 tetrahedral 4bonds 109.50bondangle
xamples identifying hybridization



C s y
spa
y
Ionpairsareconsideredasabond



spa 1s

of
upthespace onebond
doubletriplebondstake



molecular
orbitals

constructiveinterference

molecularorbitalformedismorestablethaneitheratomicorbital

calleda molecularorbital
bonding
destructiveinterference

molecularorbitalformedislessstable
than atomicorbitals
original
calledantibondingmolecularorbital alwayscontainnodes

esonancestructure

resonancestructureiscreated
byelectronmovement thereforethecurvedarrowscanbeusedtotrackhowth
electronsare
being
delocalizedwithin themolecule
electronsflowfrom electrondensitytolowdensity
high
Keyguidelines
1 neverbreaka bond
single
2 moveonlylonepairelectronsor it bond electrons
pi
3 neverexceedtheoctetforsecondrowelements CNOandF

4 theuse two ormore curvedarrowsisallowedonly thesecondarrowremovesthe
of if

, violationfromthefirstarrow

5 thenetformal
chargeofthe
resonance structuresmustremainthesame

example




e e s
r n



i t
e s e s chargeismoststableonthemost electronegative

n atom C
thebond
afterbreaking

chargeonthecarbon
electronsaremoved positive


chapter2acids
andbases
Arrheniusdefinition

acidsubstancethatproducesHtions

basesubstancethatproducesonions

BronstedLowrydefinition

acidprotondonor

baseprotonacceptor

lewisdefinition

acidsubstancethatacceptselectrons

basesubstancethatdonateselectrons