It is pdf of covalent bond

1. COVALENT BOND
Covalent bond: The bond which is formed by mutual sharing of valance electrons.
 The bond which is formed between only in non-metals.
 These electrons are simultaneously attracted by the two atomic nuclei.
 . A covalent bond forms when the difference between the electronegativities of two atoms is too
small for an electron transfer to occur to form ions.
Examples
H2 , Cl2 , H20 , CH4 , NH3 , HCL , CH3OH , C2H4 , O2 , Co2 , N2 , CCl4
TYPES OF COVALENT BOND
There are four types of covalent bond.
 Single covalent bond
 Double covalent bond
 Triple covalent bond
 Giant covalent bond
Formation of Covalent bond :
By dot and cross structure
Single covalent bond:
H2 , Cl2 , F2 , H2O , NH3 , HCL etc

2. H2 Hydrogen gas ( Hydrogen molecule )
H1 k
H1 1
Cl2 chlorine gas
Cl17 K L M
2 8 7
F2 Florine gas
F9 K L
2 7
H20 Water
H1 K L
1
O8 2 6

3. NH3 Ammonia
N7 K L
2 5
H1 1
HCL Hydrochloric Acid
H1 K L M
1
Cl17 2 8 7
Double covalent: each element shared mutual ( two e^2- )
Examples: O2 , Co2 etc
O2 Oxygen gas
O8 K L
2 6

4. Triple Covalent bond: Each element shared mutual ( three electrons )
Examples: N2 etc
N2 Nitrogen gas
Properties of Covalent compounds
 Covalent is a weak bond, because they have weak rander wall forces ( molecular forces)
 Covalent compounds mostly gases, liquid and soft solids.
 They have low melting and boiling point.
 They are insulator ( non-conductor ) of heat and electricity.
 They are insoluble in water but soluble in organic solvent.