CBSE Class 11-science Answered

1. Draw the Lewis structure of the molecule.
2. Determine the number of groups (bonds) around the central metal atom and the number of lone pairs on the central metal.
3. The valence shell configuration of the central atom should also be known.

For example: In C₂H₄, the carbon atom is surrounded by 3 groups. The valence shell configuration of C is 2s² 2p². Therefore, one s and two p orbitals are mixed to give 3 sp² hybrid orbitals.

There is one more method which applies to some molecules for determining the hybridization.

Hybridisation is given by the formula:

H=1/2[ V + X - C + A]

Where V= number of valence electrons in central atom, X=number of monovalent atoms around the central atom, C= +ve charge on cation and A= -ve charge on anion

For example in H₂SO₄, to find the hybridization of sulphur:

V = 6, X = 2, C = 0, A = 0

H = ½[6+2] = 4 = sp³

In above structure, the two oxygen atoms are considered as coordinated bonded and treated as single bond. Use the following table to match the possible values of H with the corresponding hybridisation

If , n=2 hybridisation is sp

n=3 hybridisation is sp²

n=4 hybridisation is sp³

n=5 hybridisation is sp³d

n=6 hybridisation is sp³d²