1.  Hybridization 1s Overlap of 1sH-1sH s-bond
How is the bond formed in H2 molecule?
H● + ●H → H-H H ● 1s
Overlap of 1sH-1sH
Increase in the electron density on the line connecting the two nuclei. 
s-bond

2. s-bond How is the bond formed in HF molecule?
H● + ●F → H-F
Overlap of 1sH-2pF
s-bond
How is the bond formed in F2 molecule?
Overlap of 2pF-2pF

3. How is the bond formed in CH4 molecule?
Problem: Only two unpaired electrons in C atom!! CH2!!!!
Now: 4 unpaired electrons in C atom  4 bonds! 2s 1s 2p
Problem: bonds are not equivalent:
1 bond
3 bonds

4. Bond angle H-C-H = 90º NOT 109.5º
can not be correct!
Hybridization

5. No. of hybrid orbitals = No. of mixed orbitals

6. N H How is the bond formed in NH3 molecule?2p N H
Overlap of 1sH-2pN??
Problem: bonds are perpendicular to each other!! N
3 bonds
Actually 107º which is close to º not to 90 º.

7. 2s 1s 2p
Overlap of sH-sp3N 2s 1s 2p O H
Bond angle 90º!!

8. No. of mixed orbitals = No. of s bonds + No. of lone EP
CH4: 4+0 = 4 (1 s + 3 p) = 4 sp3
NH3: 3+1 = 4 (1 s + 3 p) = 4 sp3
H2O: 2+2 = 4 (1 s + 3 p) = 4 sp3

9. p-BOND
Increase in electron density above and below the connecting line.

10. the fourth is different.
How is the bond formed in C2H4 molecule? 2s 1s 2p
120º
3 equivalent bonds,
But the three bonds must be perpendicular!!
3 equivalent bonds,
the fourth is different.
Only two bonds.

14. What is the hybridization of C atom in C2H4? sp2
no. of s-bonds=3 no. of lone EP=0
3+0=3 one s + two p → sp2

15. Only two bonds are equivalent.
How is the bond formed in C2H2 molecule? 2s 1s 2p
3 equivalent bonds,
and the three bonds must be perpendicular!!
Only two bonds are equivalent.

16.    

18. Overlap of sH-spC Overlap of spC-spC Overlap of pC-pC
What is the hybridization of C atom in C2H2? sp
no. of s-bonds=2 no. of lone EP=0
2+0=3 one s + one p → sp

19. How is the bond formed in PCl5 molecule?
Cl P Cl
Cl Cl
5 equivalent bonds. 3s 3p 3d 3s 3p 3d 3d
sp3d

20.   
Overlap of pCl-sp3dP
Overlap of sp3Cl-sp3dP

21. How is the bond formed in SF6 molecule?
F F
F S F
6 equivalent bonds. 3s 3p 3d 3s 3p 3d 3d
sp3d2

22.   
Overlap of pF-sp3d2S
Overlap of sp3F-sp3d2S

23. disordered tetrahedral
Key number
No. of mixed orbitals = No. of s bonds + No. of lone EP
Key number
Hybridi-zation
Group
Type
Molecular Geometry 2 sp
AX2
linear 3
sp2
AX3
planar triangular
AX2E
V-shaped 4
sp3
AX4
tetrahedral
AX3E
trigonal pyramidal
AX2E2 5
sp3d
AX5
trigonal bipyramidal
AX4E
disordered tetrahedral
AX3E2
T-shaped
AX2E3 6
sp3d2
AX6
octahedral
AX5E
square pyramidal
AX4E2
square planar

24. Exercise: Explain the bonds in N2, CO2, BF3?
H-F
What is the hybridization of F in HF?
No. of mixed orbitals = No. of s bonds + No. of lone EP
= = 4
HF bond is formed by the overlap of sH with sp3F
Better than overlap of 1sH-2pF
In sp3 hybridization, the repulsion between the lone EPs around the F atom is less than that in the unhibridized atom (Lone EPs in p-orbitals are only 90º away from each other).
Exercise: Explain the bonds in N2, CO2, BF3?