classroom
activity
7
Hybridization Affects Acidity and Basicity
of a Molecule
Show You Know!
1. Generate electron occupation vs. energy diagrams as shown in Model 2 for each of the following:
a. Ground state oxygen and nitrogen
Energy
Shell 2
2px
2py
2pz
Potential Energy
Energy
Shell 2
2s
Energy
Shell 1
2py
2pz
2 px
Energy
Shell 2
2s
Energy
Shell 1
1s orbital
Ground State Carbon
Energy
Shell 1
1s orbital
1s orbital
Note: These are the two pairs
of nonbonded electrons
2pz
2py
2px
2pz
Potential Energy
Hybridize
2sp2
2sp2
2sp2
2s
Energy
Shell 1
1s orbital
1s orbital
Oxygen with sp2 hybridized
valence orbitals
Ground State Oxygen
1s22s22p4
c.an sp hybridized nitrogen
Note: These are the
nonbonded electrons
Energy
Shell 2
2pz
2py
2px
2 py
2pz
Potential Energy
Hybridize
2sp
2sp
2s
Energy
Shell 1
1s orbital
Ground State Nitrogen
1s22s22p3
2 px
Ground State Oxygen
1s22s22p4
b.an sp2 hybridized oxygen
Energy
Shell 2
2py
2s
Ground State Nitrogen
1s22s22p3
1s22s22p2
2pz
1s orbital
Nitrogen with sp hybridized
valence orbitals
Note: These are the
electrons that are
in covalent bonds
with other atoms
3. Explain why the C-C bond found in ethane can spin on its axis, but not the C-C bonds found in
ethene and ethyne.
In ethane, rotation of the C-C bond does not effect the overlap of the orbitals forming σ bond.
In ethene, there is a σ bond and a π bond. Theoretically, one could still rotate the σ bond, however,
rotation of the C-C bond affects the overlap of the orbitals forming π bond. When the p orbitals
no longer overlap the π bond breaks. As we have said before in this class, breaking bonds requires
energy, and this results in a molecule with a higher potential energy, and decreased stability.
The same is true for ethyne, but now there are two sets of p orbital overlap forming the two π
bonds.
7 Hybridization affects acidity and basicity of a molecule
5. For a carbon that is sp hybridized, how many sp hybrid orbitals would you expect to find in the
second energy shell?
If the carbon is sp hybridized, you would expect 2 sp hybrid orbitals. Ethyne has the ability
to make 2 sigma bonds, each comes from an orbital that has some s character.
7. Non-bonded electrons can be found in
hybridized or unhybridized orbitals.
For each lone pair in the molecules at
right, identify the type of orbital where
the electrons are found.
H
N
sp2
sp3
H
Cl sp
sp3
3
H
s