Flashcards for JEE Chemistry - Chemical Bonding and Molecular Structure Class 11

 Page 1


Chemical Bonding & Molecular Structure
Flash cards
Page 2


Chemical Bonding & Molecular Structure
Flash cards
Chemical Bond
The force of attraction which hold various constuents (atom, 
ions etc) together in different chemical species is called a 
chemical bond.
Page 3


Chemical Bonding & Molecular Structure
Flash cards
Chemical Bond
The force of attraction which hold various constuents (atom, 
ions etc) together in different chemical species is called a 
chemical bond.
Cause of Chemical Bond
(i) Tendency to acquire noble gas configuration :
(a) Noble gases do not react with other elements due to most 
stable configuration (8 electrons in outer most shell).
(b) So the remaining elements also try to acquire the same by 
loosing, gaining or sharing of electrons.
(c) Lewis octet rule : The tendency of atoms to achieve 
eight electrons in their outermost shell is known as Lewis octet 
rule.
(d) Exception of Octet Law : PCl
5
, SF
6
, IF
5
, IF
7
, ClO
2
, BF
3
, 
AlCl
3
, GaCl
3
, BeCl
2
.
(ii) Tendency to acquire minimum energy.
Page 4


Chemical Bonding & Molecular Structure
Flash cards
Chemical Bond
The force of attraction which hold various constuents (atom, 
ions etc) together in different chemical species is called a 
chemical bond.
Cause of Chemical Bond
(i) Tendency to acquire noble gas configuration :
(a) Noble gases do not react with other elements due to most 
stable configuration (8 electrons in outer most shell).
(b) So the remaining elements also try to acquire the same by 
loosing, gaining or sharing of electrons.
(c) Lewis octet rule : The tendency of atoms to achieve 
eight electrons in their outermost shell is known as Lewis octet 
rule.
(d) Exception of Octet Law : PCl
5
, SF
6
, IF
5
, IF
7
, ClO
2
, BF
3
, 
AlCl
3
, GaCl
3
, BeCl
2
.
(ii) Tendency to acquire minimum energy.
Electrovalent Bond (Continued)
(a) Condition necessary for formation of ionic crystal :
[EA + Lattice Energy] > [Sublimation Energy + IP + (Bond 
dissociation E/2)]
Page 5


Chemical Bonding & Molecular Structure
Flash cards
Chemical Bond
The force of attraction which hold various constuents (atom, 
ions etc) together in different chemical species is called a 
chemical bond.
Cause of Chemical Bond
(i) Tendency to acquire noble gas configuration :
(a) Noble gases do not react with other elements due to most 
stable configuration (8 electrons in outer most shell).
(b) So the remaining elements also try to acquire the same by 
loosing, gaining or sharing of electrons.
(c) Lewis octet rule : The tendency of atoms to achieve 
eight electrons in their outermost shell is known as Lewis octet 
rule.
(d) Exception of Octet Law : PCl
5
, SF
6
, IF
5
, IF
7
, ClO
2
, BF
3
, 
AlCl
3
, GaCl
3
, BeCl
2
.
(ii) Tendency to acquire minimum energy.
Electrovalent Bond (Continued)
(a) Condition necessary for formation of ionic crystal :
[EA + Lattice Energy] > [Sublimation Energy + IP + (Bond 
dissociation E/2)]
Electrovalent Bond (Continued)
(b) Born Haber cycle :
The energy changes involved in the formation of ionic 
compounds from their constituent elements can be studied 
with the help of a thermochemical cycle called as Born-
Haber cycle.
e.g.: Formation of 1 mole of NaCl from sodium and chlorine
?H
f
= S.E + 1/2 D.E + I.E – E.A – u
If ?H f value is more negative, more stable is the formed 
product.