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Name:____________________
Please Circle: Section AQ1 or AQ2
Chem 102- Summer 2007
Quiz 2
1.
a. Draw the Lewis structure of TeF5-.
b. Describe the geometry (linear, trigonal planar, tetrahedral, trigonal bipyramidal,
octahedral)
c. Describe the molecular shape
d. Label (above) and approximate bond angle(s) between the central atom and the
surrounding atoms in the drawing of TeF5-.
2. Which of the following statements is false concerning bonding?
a) In a C-O bond, electron density on the average is greater near the O atom.
b) A C-O bond is an example of a polar covalent bond.
c) Elements with extremely different electronegativity values tend to form ionic bonds with
each other.
d) An N-H bond is more polar than a P-H bond.
e) None of the above statements (a-d) are false.
3. Two different compounds have the formula SF4Cl2 (where S is the central atom). Which of the
following statements concerning the two SF4Cl2 compounds is false?
a) The central atom in both compounds of SF4Cl2 exhibit d2sp3 hybridization.
b) Both compounds of SF4Cl2 exhibit some 90º bond angles.
c) Both compounds of SF4Cl2 have an octahedral shape.
d) Both compounds of SF4Cl2 are exceptions to the octet rule for at least one of the atoms in
the formula.
e) None of the above statements (a-d) are false.
4. Which of the following statements is false?
a) The three 6p atomic orbitals have the same energy but they differ in their orientation
about the x, y, and z axes.
b) 2d atomic orbitals do not exist in the quantum mechanical model of the atom.
c) For neutral charged atoms, the 8s atomic orbital should be lower in energy than the 7d
atomic orbitals.
d) The dx2 atomic orbital has a unique shape as compared to the other four d atomic orbitals.
e) None of the above statements (a-d) are false.
2
5. Which of the following compounds will be least soluble in water? Hint: Water is a polar
solvent and “like dissolves like”.
a) IF5
b) PF3
c) KrF2
d) COS
e)SO2
6. Which of the following molecules have at least one 90º bond angle in their structure as
predicted by the VSEPR model?
a) H—C—C—H
b) H—C—N
c) F—O—F
d) CH2O
e) None of the molecules above have a 90º bond angle.
7. How many of the following molecules have a square planar shape?
KrF4, PCl5, XeO4, TeF4, ICl3
a) 1
b) 2
c)3
d) 4
e) 5 (All have square planar shape.)
8. Which of the following compounds are ionic and which are covalent? (Write I or C next to
the compound name)
a) water
b) ammonia
c) sodium oxide
d) potassium nitrate
e) sulfur trioxide
f) manganese(IV) sulfide
g) carbon tetrachloride
9. List the following from lowest to highest ionization energy.
Ba, Cu, Ne
10. Draw the Lewis structure, determine the geometry and predict the shape for each of the
following molecules:
a) H20
d) NH3
b) BrF3
e) NH4+
c) XeOF4
f) NO3-