Page 10 - Pharm.Org.Chem I 05-PC101 (1)

Valency

The number of electrons an atom must lose or gain to
attain the nearest noble gas electronic configuration.

2px1 2py1 2pz
2s2
promotion

2px1 2py1 2pz1
2s1
Thus C is tetravalent

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2p 1 2p 1 2pz1 sp3
sp2
x y

2s1 sp3 sp3 sp3 sp3

2px1 2py1 2pz1 2py
sp2 sp2 sp2

2s1

2p 1 2p 1 2p 1 sp

x y z 2py 2pz

sp sp

2s1 This is called Hybridization

Energy level of hybridized orbitals is between that of s and p orbitals

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