Quiz 4
1)
Chemistry 172
(Winter 08-09)
Name _____________________
Predict whether a sigma (s), pi (p), or no bond (n) forms from the following orbitals coming together on the x axis.
a) px and py __n___
b) px and px __s___
c) sp3 and s __s___
d) sp3 and px __s___
e) sp2 and sp __s___
e) sp3 and py __n___
For 2-4, refer to the structure below:
2)
There are ___13______ sigma bonds and
_____3_____ pi bonds.
3)
Identify the expected hybridization of each atom.
A (carbon) __sp____
B (carbon) ___sp2____
C (nitrogen) ___sp3____
4)
Provide the value of each indicated angle.
1 (C-C-C) _180__
5)
6)
2 (C-C-C) _120__
3 (C-N-H) _109.3___
As the number of bonds between two carbons increases, which one of the following decreases?
a) number of electrons between the carbon atoms
b) bond energy
c) bond length
d) formal charge
Draw the number and relative energy of 2s and 2p orbitals of an atom before hybridization and the number and
relative energy levels of the orbitals that are formed in the atom after sp hybridization
before hybridization
2p ____ _____ _____
after hybridization
2p ____ _____
sp ____ _____
2s ____
7)
Provide a rationale as to why the 1s orbitals are not included in the formation of hybrid orbitals.
Valence electrons are not in the 1 s orbitals and not involved in bonding.
They are smaller than the 2s and 2p orbitals and may not combine as well
8)
Identify the type of hybridization in the oxygen and the carbons below. Describe what orbitals are employed to
form each of the bonds in this molecule.
O is sp3 hybridized and C is sp2 hybridized
The sp3 orbitals of O form a σ bond with the 1s of H and with the sp2 of C
The sp2 orbitals of the right C form σ bonds with 1s of H, sp3 of O, and sp2 of the other C.
The sp2 orbitals of the left C form σ bonds with 1s of H, sp2 of the other C
The unhybridized p of each C forms a π bond.
9)
For each molecule below provide the requested information in the appropriate blank.
A correct Lewis dot structure is required to answer these correctly.
a) SeO3
b) PF3
c) SF4
d) SiCl4
e) HCN
f) PCl5
g) IF5
______sp2______ hybridization
__non-polar______ polar or non-polar
trigonal planar_ electron arrangement
trigonal planar molecular shape
_____sp3_______ hybridization
__polar___ polar or non-polar
tetrahedral____ electron arrangement
trigonal pyramidal molecular shape
____dsp3______ hybridization
polar________ polar or non-polar
trigonal bipyramidal electron arrangement
seesaw_______ molecular shape
___sp3_________ hybridization
_ nonpolar_ polar or non-polar
_tetrahedral___ electron arrangement
_tetrahedral molecular shape
_sp__________ hybridization
___polar______ polar or non-polar
_linear_______ electron arrangement
__linear______ molecular shape
_dsp3_________ hybridization
_nonpolar__ polar or non-polar
trigonal bipyramidal electron arrangement
trigonal bipyramidal molecular shape
___d2sp3_______ hybridization
_polar_______. polar or non-polar
octahedral_ electron arrangement
_square pyramidal_ molecular shape
a) SeO3
b) PF3
c) SF4
d) SiCl4
e) HCN
f) PCl5
g) IF5
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________ polar or non-polar
______________ electron arrangement
______________ molecular shape
______________ hybridization
______________. polar or non-polar
______________ electron arrangement
______________ molecular shape