CHAPTER -O4
CHEmi CAL BoNDING, 4ND moLE CULAR STRUCTURE
eHEMlCA L &oND The attYactue
torces wich holols
bogther thee constituent ptticles (atoms,
lond
bond
or molecules )
in a chemical specis kycan as chonmica )
Leois symbols Gy Lewi8 Gn
N , Amesican chemist intoduded
bimple notatin to eprejent valence electrom
m atom these notation& au eallead kews ymbol4
wlich ae given belbww
Li Be 6. Na Al: Si.
TYPE OF BONDS :
hene ce three type of bond
(D Jonic bond covaleut bernd (0) (oovdjnaute bone
(2)
1ONIC 80ND! Such dype of bond is tor mad by Hue
+ranso o electron rom one ator to ths rt nesut
Po the formtiern of Cattons emd anjons formahon o te
/onic bond is Srerezendel belo o
Na
882 3 lon'e Corboundl
Na Net +e
1s2,283, 2 (3823b6 wel3s CNe]
Ne] ast sbS
(2) covolent bomd! the yomaton o such type ot bmd
Ja ke place by shasing of'eleotron.
, the Yormation of Covalent bnds is represenkeel balouws
0::0:
(3) Coodinate bond: In juch a bond t electvon as
Shareol ondy oy ons atom, Hee otleor one doeS not shau
omy electoo
0CTET RULE
AHoms Combin itr by transex of
electron Hrom one
valente
|afom o
another l guining or Joning) or y
shaning o valence alettrer
dn order to haue octet in ther valencershall , tis is (alled octet
ule
ExcepHon of the octel ue
0
|(2)
Hydrogen molecues
Jnlomtlete octet of
HH
he
H-H
(ental atom
H
ka,LoI
ede. /
(3)
ExpamdleclBM,
central DCtet of he
8
atom
2 3
Exaple PEs
X
K
() odel zlectron mplecule '
O=N-0:
Nitoic oxide
(6) re moy he noteel tlat Jhe bctet rule besesl pon
, Committed for Excellence in Education 9911274975
Phe chaiccl mrtness of noble g ases Hou evor, it kas been
found that some noble gases Cespecialy xenon onnd kryptn)
also Combine with oygen omdd leoint to form a Birqe
umbe of Compoumls such as XeFz,Krß, xeof ,XeoFa y
Xe Fe etc
FORMAL CHARbE:
7he Yormal charge e pody ctomic ton or meleculs
of an etom in
is cdatPnecd asbetween
he umber of valence
oliyference lem
electron in an sodatal Cor free) atom orndl the numbor of
electron assighel to hat atom in kewio structn a
Number of valence Noof mon bondiny)
omal charg electron in fre -electaren
atom
oo
electon
beneling)
Simply
formal chorgec
Valenee eleco on
Lav2epaur o Nen bon ding electros
S Shered leeo on
Latttce thaloy of onic Cystal
En H
deineelas'
Ltlice cn thalloy tomt crystel is
energy eleasecl when one mole of
e The gmount of
sfat"
from its Consh tuent ons in Hs gascous
formed
AH latlite en halby =
mi9) 9)
as
lattice en ha/by also lefineel
Dn the oflerhand sep erat one nle
omhl etely
le engy required
mc
to
Combouncd into gacous lom'c
ofsotd a
Constfyent" AH =tlut
CHEmi CAL BoNDING, 4ND moLE CULAR STRUCTURE
eHEMlCA L &oND The attYactue
torces wich holols
bogther thee constituent ptticles (atoms,
lond
bond
or molecules )
in a chemical specis kycan as chonmica )
Leois symbols Gy Lewi8 Gn
N , Amesican chemist intoduded
bimple notatin to eprejent valence electrom
m atom these notation& au eallead kews ymbol4
wlich ae given belbww
Li Be 6. Na Al: Si.
TYPE OF BONDS :
hene ce three type of bond
(D Jonic bond covaleut bernd (0) (oovdjnaute bone
(2)
1ONIC 80ND! Such dype of bond is tor mad by Hue
+ranso o electron rom one ator to ths rt nesut
Po the formtiern of Cattons emd anjons formahon o te
/onic bond is Srerezendel belo o
Na
882 3 lon'e Corboundl
Na Net +e
1s2,283, 2 (3823b6 wel3s CNe]
Ne] ast sbS
(2) covolent bomd! the yomaton o such type ot bmd
Ja ke place by shasing of'eleotron.
, the Yormation of Covalent bnds is represenkeel balouws
0::0:
(3) Coodinate bond: In juch a bond t electvon as
Shareol ondy oy ons atom, Hee otleor one doeS not shau
omy electoo
0CTET RULE
AHoms Combin itr by transex of
electron Hrom one
valente
|afom o
another l guining or Joning) or y
shaning o valence alettrer
dn order to haue octet in ther valencershall , tis is (alled octet
ule
ExcepHon of the octel ue
0
|(2)
Hydrogen molecues
Jnlomtlete octet of
HH
he
H-H
(ental atom
H
ka,LoI
ede. /
(3)
ExpamdleclBM,
central DCtet of he
8
atom
2 3
Exaple PEs
X
K
() odel zlectron mplecule '
O=N-0:
Nitoic oxide
(6) re moy he noteel tlat Jhe bctet rule besesl pon
, Committed for Excellence in Education 9911274975
Phe chaiccl mrtness of noble g ases Hou evor, it kas been
found that some noble gases Cespecialy xenon onnd kryptn)
also Combine with oygen omdd leoint to form a Birqe
umbe of Compoumls such as XeFz,Krß, xeof ,XeoFa y
Xe Fe etc
FORMAL CHARbE:
7he Yormal charge e pody ctomic ton or meleculs
of an etom in
is cdatPnecd asbetween
he umber of valence
oliyference lem
electron in an sodatal Cor free) atom orndl the numbor of
electron assighel to hat atom in kewio structn a
Number of valence Noof mon bondiny)
omal charg electron in fre -electaren
atom
oo
electon
beneling)
Simply
formal chorgec
Valenee eleco on
Lav2epaur o Nen bon ding electros
S Shered leeo on
Latttce thaloy of onic Cystal
En H
deineelas'
Ltlice cn thalloy tomt crystel is
energy eleasecl when one mole of
e The gmount of
sfat"
from its Consh tuent ons in Hs gascous
formed
AH latlite en halby =
mi9) 9)
as
lattice en ha/by also lefineel
Dn the oflerhand sep erat one nle
omhl etely
le engy required
mc
to
Combouncd into gacous lom'c
ofsotd a
Constfyent" AH =tlut
