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    SHAPES OF

    MOLECULESChemistry

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    Recall that:Covalent bonds are formed from theoverlap of two atomic orbitals

    Each pair of covalent bond contains a pairof electrons

     Two types of covalent bonds:1. Sigma (σ) bonds

    . !i bonds (") bonds

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    Electron Pairs#n molec$les thereare types ofelectron pairs

    1. %onding !airs

    . &on'bonding orlone pairs

    . The bonding pairmay berepresented by aline

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    What is the shape of the

    molecule?e will $se the geometric arrangementof atoms around a central atom in acovalent compo$nd (or charged ion) to

    determine the shape of the molec$le

    pi ' bonds have a very limited impact on

    shape

    sigma'bonds have a m$ch more importanteect

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    alence Shell Electron PairRepulsion !SEPR" #heor$

    The VSEPR theory proposes that shape of themolecule is determined solely by the

    repulsions between electron pairs present inthe valence shell of the central atom

    • The n$mber of electron pairs aro$nd the centralatom can be determined by writing the *ewisstr$ct$re for the molec$le

    • +SE!, theory is a model that helps $s to$nderstand the -' str$ct$re of molec$les

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    #he SEPR Mo%el

    • +SE!, theory can be $sed to predict the shapesand bond angles of molec$les and molec$lar ions

    !airs of electrons that s$rro$nd the central atom ofa molec$le or ion are arranged as far apart aspossible to minimi/e electron'electron rep$lsion

    0pplicable only to covalent compo$nds (#onicbonds are non'directional while covalent bondshave a preferred direction in space)

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    SEPR #heor$ an% Repulsion

    Electrostatic force of rep$lsion betweenelectron pairs

    ,ep$lsion occ$rs to attain most

    comfortable arrangement Three types of rep$lsion to consider:

    1. %onding pair ' %onding pair rep$lsion

    . *one pair ' *one pair rep$lsion-. %onding pair *one pair rep$lsion

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    Stren&th of Repulsion• epends on pro2imity of electron pairs to central atom

    • %onding pairlocated between two n$clei

    • *one pairs closer to central atom

     they are delocali/ed

    have no other n$cle$s to attract them

    • *one pairs p$sh bond pairs closer0s bonds are p$shed closer together the bond angle decreases

    LP'LP REPULS(O)S * LP'+P REPULS(O)S * +P'+P REPULS(O)S

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    Molecular ,eometries

    #-o Electron Pairs

    #hree Electron Pairs

    Four Electron Pairs

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    Fi.e ElectronPairs

    Si/ ElectronPairs

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    Molecular ,eometries !Cont0%"

    Se.en Electron Pairs

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    Usin& SEPR theor$ to pre%ict the shapeof the molecule

    1. ecide which is the central atom in a molec$le.#n cases of ambig$ity3 pic4 the leastelectronegative atom (aside from hydrogen) asthis atom will be better able to share its

    electrons with the other atoms in the molec$le

    . Co$nt $p the valence electrons on the centralatom.

    -. Co$nt $p the electrons $sed by the o$ter atomsto ma4e bonds with the central atom

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    Usin& SEPR theor$ to pre%ict the shapeof the molecule

    5.  The s$m of steps () 6 (-) divided by two givesthe +alence Shell Electron !air (+SE!) co$nt

    The VSEP count gives the number of electron pairs around the central atom

    7. 0ssign one electron pair for each bond (or twopairs for each do$ble bond). 0ny $nassignedelectron pairs are lone pairs and are placed onthe CENTRA atom.

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    SEP Count

     The predicted geometry of the molec$le is basedon the n$mber of +SE! co$nt i.e. the arrangementof E! aro$nd the central atom (both lone pair andbonded pair)

    Eg. Calc$late the +SE! co$nt for the watermolec$le

    1. Central 0tom is 82ygen. &$mber of valence electrons 9 e'

    -. &$mber of electrons $sed byperipheral atoms to bond to centralatom 9 (1) 9 e'

    +SE! co$nt 9 ( e') 6 ( e') ; 9 5 e' pairsThe ! central atom has " e# pairsaround it 

    $ bonding pairs and $ non#bonding

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    Pre%ictin& the Shapes of

    Molecules%eClhat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is %erylli$m

    &$mber of valence electrons 9 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 (1) 9 e'

    +SE! co$nt 9 ( e') 6 ( e') ; 9 e' pairs

    •The 'e central atom has $ e# pairs around it 

    •$ bonded pairs and N! non#bonded or lone pairs

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    Pre%ictin& the Shapes of

    Molecules+eCl1hat is the shape of themolec$le< %ond angle<

    %ond 0ngle 9 1>??

    *inear Shape

    #n generalmolec$les 3 0@3 with

    $ bonding pairsand no lone pairs 

    are *inear.

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    Linear Molecules !A21"

    hen applying the +SE!, model3 we count a double ortriple bond as a single electron domaino$ble and triple bonds are linear3 and behave very m$chli4e a single bond when it comes to rep$lsions

    What is the structure of C1H1?

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    Pre%ictin& the Shapes of

    Molecules%A-hat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is %oron

    &$mber of valence electrons 9 - e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 - (1) 9 - e'

    +SE! co$nt 9 (- e') 6 (- e') ; 9 - e' pairs

    •The ' central atom has ( e# pairs around it 

    •( bonding pairs and N! non#bonding or lone

     pairs

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    Pre%ictin& the Shapes of

    Molecules+F3hat is the shape of themolec$le< %ond angle<

    %ond 0ngle 9 1??

     Trigonal !lanar

    #n generalmolec$les 3

    0@-3 with (bonding pairs and no

    lone pairs are Trigonal

    Planar 

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    #ri&onal Planar !A23"

    )* Show that %a& N!(# and %b& S!(

     

    display a trigonal planar

    arrangement 

    E2amples incl$de &8-'3 S8-3 C8-' andC=5

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    Pre%ictin& the Shapes of

    MoleculesC=5hat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is Carbon

    &$mber of valence electrons 9 5 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 5 (1) 9 5 e'

    +SE! co$nt 9 (5 e') 6 (5 e') ; 9 5 e' pairs

    •The C central atom has " e# pairs around it 

    • " bonding pairs and N! non#bonding or lone

     pairs

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    Pre%ictin& the Shapes of

    MoleculesCH4hat is the shape of themolec$le< %ond angle<

    %ond 0ngle 9 1?B.7?

     Tetrahedral

    #n general molec$les 30@53 with " bonding

     pairs and no lone pairs are Tetrahedral 

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    #ri&onal Planar !A24"

    )* Show that the following moleculeshave a tetrahedral structure+

    a&N, "-

     b&S! "$# 

    c& P! "(#

    d&Ni%C!& "e&C, "

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    Pre%ictin& the Shapes ofMolecules&=-hat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is &itrogen

    &$mber of valence electrons 9 7 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 - (1) 9 - e'

    +SE! co$nt 9 (7 e') 6 (- e') ; 9 5 e' pairs

    •The N central atom has " e# pairs around it 

    •( bonding pairs and . non#bonding or lone pair 

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    Pre%ictin& the Shapes ofMolecules)H3

    hat is the shape of themolec$le<

    %ond 0ngle 9 1??

     Trigonal !yramidal

    #n general molec$les 30@-E3 with ( bonding

     pairs and . lone pairare Trigonal Pyramidal 

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    #ri&onal P$rami%al

    )* Show that the following moleculeshave a trigonal pyramidal structure+

    a&P,( 

    b&S!($# 

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    Pre%ictin& the Shapes ofMolecules=8hat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is 82ygen

    &$mber of valence electrons 9 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 (1) 9 e'

    +SE! co$nt 9 ( e') 6 ( e') ; 9 5 e' pairs

    •The ! central atom has " e# pairs around it 

    •$ bonding pairs and $ non#bonding or lone pairs

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    Pre%ictin& the Shapes ofMoleculesH1O

    hat is the shape of themolec$le< %ond angle<

    %ond 0ngle 9 1?5.7?

    %ent (or +'shaped)

    #n general

    molec$les 3 0@E3

    with $ bonding pairs and $ lone

     pairs are 'ent or V#shaped 

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    +ent or 'shape% molecules

    )* Show that the following moleculeshave a bent structure+

    a&,$Sb&S!$

    c& ,$!

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    Pre%ictin& the Shapes ofMolecules!Cl7hat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is !hosphor$s

    &$mber of valence electrons 9 7 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 7 (1) 9 7 e'

    +SE! co$nt 9 (7 e') 6 (7 e') ; 9 7 e' pairs

    •The P central atom has / e# pairs around it 

    •/ bonding pairs and N! non#bonding or lone

     pairs

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    Pre%ictin& the Shapes ofMoleculesPCl5hat is the shape of themolec$le< %ond angle<

    %ond 0ngle 9 B?? and 1??

     Trigonal %ipyramidal

    #n general

    molec$les 3 0@73 with

    / bonding pairsand 0 lone pairs

    are Trigonal'ipyramidal 

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    Pre%ictin& the Shapes ofMoleculesSAhat is the +SE! co$nt< =ow many bonding pairsand lone pairs<Central 0tom is S$lph$r

    &$mber of valence electrons 9 e'

    &$mber of electrons $sed by peripheral atoms tobond to central atom 9 (1) 9 e'

    +SE! co$nt 9 ( e') 6 ( e') ; 9 e' pairs

    •The S central atom has 1 e# pairs around it 

    •1 bonding pairs and N! non#bonding or lone

     pairs

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    Pre%ictin& the Shapes ofMoleculesSF6hat is the shape of themolec$le< %ond angle<

     The A'S'A %ond 0ngles areall B?? 

    8ctahedral

    #n general molec$les 3 0@3

    with 1 bonding pairs and 0lone pairs are !ctahedral 

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    SHAPES A)7 +O)7A),LES OF S(MPLEOR,A)(C COMPOU)7S

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    Or&anic

    Compoun%s!rganic compounds belong to a large classof chemical compounds whose moleculescontain carbon %e2cept C!$ and carbonates&

     The simple pict$re of overlap of half'Dlledatomic orbitals cannot be $sed to e2plain thegeometry of all molec$les especially organicmolec$les

    e $se a concept 4nown as hybridi3ation toe2plain bonding in carbon compo$nds

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    Methane !CH4"Carbon needs to have fo$r singlebonds

    &eeds fo$r single electrons

    !romotion of an electron from the s

    orbital to the p orbital

    i2ing the s and p orbitals(hybridi/ation)

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    H$8ri%isation• s electronsspontaneo$sly promotedto empty p orbital

    • FsG orbital and the T=,EE FpG orbitals mi2to form A8H, hybridorbitals (sp-) with four

    single electrons

    • number of orbitals is conserved  

    during hybridisation

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    E/cite% Car8on Atom

    Ao$r identical sp- orbitals formed 0ll the same shape3 si/e and energy

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    sp3 H$8ri% Or8italsEach hybrid orbital contains 7I scharacter and 7 I p character.

     The A8H, sp- hybrid orbitals eachcontains one electron

    =ybrid orbitals arrange themselves in athree dimensional space to get as farapart as possible (to minimi/e rep$lsion)

    0rrangement gives rise to a tetrahedralstr$ct$re bond angle of 1?B.7

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    Sp3 H$8ri%i9ation !Methane"

    Overlapping of sp3 orbitals on carbon

    with s orbital of hydrogen gives rise to a

    sigma bond

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    Sp3 H$8ri%i9ation !Ethane"

    sp3 or8itals ofcar8on o.erlap-ith s or8italof h$%ro&en to&i.e a si&ma

    8on%

    sp3 or8itals on8oth car8onso.erlap to &i.e

    a si&ma 8on%

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    Sp2 Hybridization

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    Sp1 H$8ri%i9ation

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    Sp1 h$8ri%i9ationAo$nd in compo$nds s$ch as al4enes (eg ethene)

    Each carbon needs to form three bonds (twohydrogens and one carbon)

    Electron promotion still occ$rs in carbon followed bymi2ing of the s and p orbitals

    =owever3 only two of the p orbitals are mi2ed withthe s orbital to form three sp hybrid orbitals

     The $n$sed p orbital remains p$re ($nhybridi/ed)

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    sp1 H$8ri%i9ation !C1H4"

     Two sp orbitals will overlap with hydrogen 1sorbitalJ the third sporbital will overlap with asimilar sp orbital on the other carbon atom

    Each carbon has a p$re3 $n$sed p orbitalcontaining an electron

     The $n$sed p orbitals are perpendic$lar to theplane of the sp orbitalsJ proKects above and below

    the plane

    close pro2imity of p orbitals ca$ses sidewaysoverlap forming a pi bondJ !i bonds are wea4erthan sigma bonds

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    Sp2 Hybridization (Ethene)

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    Ethene

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    +en9ene

    Si2 carbon atoms in a ring

    Shows resonance hybrid

    =e2agonal in shape ' at each ape2 there is acarbon bonded to a hydrogen

    Each carbon is bonded to three other atomsJ ahydrogen and two other carbon atoms

    Each carbon $ses sp hybrid orbitals

    Each carbon contains a p$re p orbital perpendic$larto the plane of the ring

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    +en9ene

    Each $nhybridi/ed p orbital overlaps with twoother p orbitals3 one on each of the twoneighbo$ring carbon atoms

    0 large circ$lar pi'type bond is formed aboveand below the plane

    Electrons are delocali/ed in the ben/ene ring

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    +en9ene

    8verlapping of p orbitals

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    +en9ene

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    +en9ene

    Canonical forms

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    +en9ene

    =ybridi/ed str$ct$re

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    LE!"#E

    Shapes of $olec%les

    &' hemistry ower oints

    !opic

    Bonding 

     www.pedagogics.ca 

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    *reat than+s to

    ,O-.!H.- HO!O- / 0-O0H.#1 "'L&SH&-*

     www.knockhardy.org.uk/sci.htm 

      uch taken from

    AN INTRODUCTION TO

     BONDING

    and

    SHAPES OF

    OECUES

    .LE-E SHELL ELE!#O- .

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    .LE-E SHELL ELE!#O- .

    #E"LS&O- (SE#) !HEO#

    4!HE SH.E .1O!E1 ' . S&$LE $OLE"LE O# &O- &S

    !H.! 5H&H 0EES #E"LS&E 6O#ES !O . $&-&$"$7

    Molecules containco.alent 8on%s Asco.alent 8on%s consistof a pair of electrons;each 8on% -ill repelother 8on%s

    .l'onds are f%rther

    apart so rep%lsive

    forces are less

    'onds are closer

    together  so rep%lsive

    forces are greater 

    .l

    .ll bonds are

    e8%ally spaced

    o%t as far apartas possible

    -ote 9 yo% m%st

    thin+ of spacing

    in 31 not :%st 21

    +on%s -ill thereforepush each other as farapart as possi8le to

    re%uce the repulsi.eforces

    +ecause the repulsionsare e

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    .11&-* .-O!HE# .!O$ ; .-&$.!&O-

    .11&-* .-O!HE# .!O$ ; .-&$.!&O-

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    .11&-* .-O!HE# .!O$ ; .-&$.!&O-

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    2 regions of electron density

    2 'onding airs; 'E#LL&"$ HLO#&1E

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    2 'onding airs; 'E#LL&"$ HLO#&1E

    l l'e?'O-1 .S 2

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    ?

    L&-E.#

    l'e 'e ll

    'erylli%m ; has two electrons to pair %p

    hlorine ; needs < electron for AoctetB

    !wo covalent bonds are formed

    'erylli%m still has an incomplete shell

    $OLE"LES 5&!H 1O"'LE 'O-1S

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    !reat as a single region of electron density

    O OO

    arbon ; needs fo%r electrons to complete its shell

    OCygen ; needs two electron to complete its shell

    !he atoms share two electrons

    each to form two do%ble bonds

    1O"'LE 'O-1 .S 2

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    ?

    L&-E.#

    O O

    ?

    1o%ble bonds behave eCactly as single

    bonds for rep%lsion p%rposes so the

    shape will be the same as a molec%le with

    two single bonds and no lone pairs@

    !he shape of a compo%nd with a do%ble bond is calc%lated in the same way@ .

    do%ble bond repels other bonds as if it was single e@g@ carbon dioCide

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    3 regions of electron density

    3 'onding airs ; .L"$&-&"$ HLO#&1E

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    .l

    3 'onding airs .L"$&-&"$ HLO#&1E

    l

    l

    .l

    ?l

    l

    .l

    l

    l

    l

    'O-1 .S 3

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    ?

    !#&*O-.L L.-.#

    .l%mini%m ; has three electrons to pair %p

    hlorine ; needs < electron to complete AoctetB

    !hree covalent bonds are formedD al%mini%m

    still has an incomplete o%ter shell@

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    regions of electron density

    'onding airs; $E!H.-E

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    'onding airs $E!H.-E

    'O-1 .S

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    @F?

    !E!#.HE1#.L

    H H

    H

    H

    H

    @F?

    H H

    H

    H

    arbon ; has fo%r electrons to pair %p

    Hydrogen ; < electron to complete shell

    6o%r covalent bonds are formed

    and H now have complete shells

    regions of electron density ; .$$O-&.

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    g y

    .-*LE@@@ G?

    SH.E@@@ #.$&1.L

    H- -H H

    H

    'O-1 .S 3

    LO-E .S <

    !O!.L .S

    G?H

    H

    -

    H

    •   !he shape is based on a tetrahedron b%t not all the rep%lsions are the same

    •   L;' #E"LS&O-S  ';' #E"LS&O-S

    •   !he -;H bonds are p%shed closer together 

    •   Lone pairs are not incl%ded in the shapeI

    regions of electron density ; 5.!E#

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    .-*LE@@@ @F?

    SH.E@@@ 'E-!

    H

    O

    H

    H OH

    H

    'O-1 .S 2

    LO-E .S 2

    !O!.L .S

    O

    H

    O

    H

    @F?H

    O

    H

    •   !he shape is based on a tetrahedron b%t not all the rep%lsions are the same

    •   L;L #E"LS&O-S  L;' #E"LS&O-S  ';' #E"LS&O-S•   !he O;H bonds are p%shed even closer together 

    •   Lone pairs are not incl%ded in the shape

    g y

    HO5 !O 1E!E#$&-ESH.ES O6 &O-S

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    -

    'O-1 .S 3 #.$&1.L

    LO-E .S < H;-;H G?

    'O-1 .S !E!#.HE1#.L

    LO-E .S > H;-;H @F?

    -

    H

    H

    H

    -JH

    H

    H

    H -J

    'O-1 .S 2 'E-!

    LO-E .S 2 H;-;H @F?

    -

    H

    H -

    -HJ

    -H2

    ;

    -H3

    F 'onding airs (HL only) ; HOSHO#"S() 6L"O#&1E

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    6

    6

    6

    6

    6

    6

    'O-1 .S F

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    ? / >?

    !#&*O-.L '&#.$&1.L

    ?

    6

    6

    6

    6

    6

    >?

    hosphor%s ; has five electrons to pair %p

    6l%orine ; needs one electron to complete AoctetB

    6ive covalent bonds are formedD phosphor%s can

    ma+e %se of d orbitals to eCpand its AoctetB

    K 'onding airs (HL only) ; S"LH"#(&) 6L"O#&1E

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    g ( y) ( )

    6S

    'O-1 .S K

    LO-E .S >

    'O-1 .-*LE@@@

    *eometry @@@

    >?

    O!.HE1#.L

    S

    6

    6

    6

    6

    6

    6

    S%lph%r ; has siC electrons to pair %p

    6l%orine ; needs one electron to complete AoctetB

    SiC covalent bonds are formedD s%lph%r can ma+e

    %se of d orbitals to eCpand its AoctetB

    6

    6 6

    6

    S

    6

    6

    >?

    HL only ; E-O- !E!#.6L"O#&1E

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    y

    6e e

    6

    6

    6

    6

    6

    6 6

    6e

    6

    6 6

    6

    e

    .-*LE@@@ >?

    SH.E @@@ SM".#E L.-.#

    •   .s the total n%mber of electron pairs is KN the shape is '.SE1 on an octahedron

    •   !here are two possible spatial arrangements for the lone pairs

    •   !he preferred shape has the two lone pairs opposite each other 

    'O-1 .S

    LO-E .S 2

    !O!.L .S K

    S"$$.#

    6"-1.$E-!.L SH.ES l i

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    6"-1.$E-!.L SH.ES 9 no lone pairsMolecules; or ions; possessin& O)L=+O)7(), PA(RS of electrons >t into

    a set of stan%ar% shapes All the8on% pair'8on% pair repulsions aree / lF

    K O!.HE1#.L > S6K

    'O-1 ELE!#O- 'O-1.S *EO$E!# .-*LE(S) E.$LE

    . covalent bond will repel

    another covalent bond

    Effect of Lone airs on $olec%lar Shape

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    Effect of Lone airs on $olec%lar Shape

    &f a molec%leN or ionN has lone pairs on the central atomN the shapes are slightly

    distorted away from the reg%lar shapes@ !his is beca%se of the eCtra rep%lsion

    ca%sed by the lone pairs@

    'O-1 . ; 'O-1 .  P  LO-E . ; 'O-1 .  P  LO-E . ; LO-E . 

    OO O

    .s a res%lt of the eCtra rep%lsionN bond angles tend to

    be slightly less as the bonds are s8%eezed together@

    S"$$.# ; .L"L.!&-* !HE SH.E O6 &O-S

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    !he shape of an ion or molec%le is determined by@@@

    •   calc%lating the n%mber of electrons in the o%ter shell of the central species Q

    •   pairing %p electronsN ma+ing s%re the o%ter shell maCim%m is not eCceeded•   calc%lating the n%mber of bond pairs and lone pairs (regions of e; density) 

    •   %sing ELE!#O- . #E"LS&O- !HEO# to calc%late shape and bond

    angle(s)

    -ote for ions

    *   the n%mber of electrons depends on the charge on the ion

    *   if the ion is positive yo% remove as many electrons as there are positive

    charges

    *   if the ion is negative yo% add as many electrons as there are negative charges

      e..g. for 6K

    ;   add one electron to the o%ter shell of

    for l

    J  remove one electron from the o%ter shell of

    O!HE# E.$LES !O !#

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    'r6F

    6

    6 6

    6

    'r 

    6

    'r63

    6

    6

    'r 

    6

    SO

    2;

    O S

    O;

    O;

    O'O-1 .S

    LO-E .S

    SH.E

    .-*LE

    'O-1 .SLO-E .S

    SH.E

    .-*LE

    'O-1 .S

    LO-E .S

    SH.E

    .-*LE

    O!HE# E.$LES !O !#

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    'r6F 'O-1 .S F

    LO-E .S <

    SM".#E #.$&1

    .-*LES >? P>? 

    6

    6 6

    6

    'r 

    6

    66 6

    6'r 

    6

    'r63 'O-1 .S 3

    LO-E .S 2

    B!B SH.E1

    .-*LE P>?

    6

    6

    'r 

    6

    6

    6

    'r 

    6

    SO

    2;

    O

    S

    O;

    O;

    O

    O S

    O;

    O;

    O'O-1 .S

    LO-E .S >

    !E!#.HE1#.L

    .-*LE @F?

    !ES! M"ES!&O-S

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    '63

    Sil

    lK

    H2S

    SilK2;

    l

    6or each of the following ionsRmolec%lesN state the n%mber of bond pairs

    state the n%mber of lone pairs

    state the bond angle(s)

    stateN or drawN the shape

    !ES! M"ES!&O-S

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    3 bp > lp trigonal planar boron pairs %p all 3 electrons in

    its o%ter shell

     

    bp > lp @F tetrahedral silicon pairs %p all electrons in

    its o%ter shell

    bp > lp @F tetrahedral as ion is JN remove an electron

    in the o%ter shell then pair %p

     

    K bp > lp > octahedral as the ion is ; N add one electron to

    the F in the o%ter shell then pair %p

     

    K bp > lp > octahedral as the ion is 2;N add two electronsto the o%ter shell then pair %p

     

    2 bp 2 lp 2 bent planar  s%lph%r pairs %p 2 of its K

    electrons in its o%ter shell ;

    2 lone pairs are left

    '63

    Sil

    lK

    H2S

    SilK2;

    l

    6or each of the following ionsRmolec%lesN state the n%mber of bond pairs

    state the n%mber of lone pairs

    state the bond angle(s)

    stateN or drawN the shape