Chemical Bonding and Molecular Structure

Chemical bond:

Chemical bond is the attractive force, which holds various constituents (such as atoms, ions) together in different chemical species.

 

Octet rule:

Atoms tend to gain, lose, or share electrons so as to have eight electrons in their valence shells.

 

Lewis dot Structure:

Representation of molecules and ions in terms of the shared pairs of electrons and the octet rule

 

CO₃^2-→

 

NO₂^-→

 

HNO₃ →

Formal charge:

Lewis structure of O₃→  

 

 

F.C. on the O^-1 

F.C. on the O^-2 

F.C. on the O^-3

 

Limitations of the octet rule:

• Incomplete octet of the central atom

E.g. BeH₂, LiCl, BCl₃

 

 

• Odd electron molecules

E.g. NO, NO₂

 

 

• Expanded octet

E.g. PF_5…