CH 115 Fall 2014
Mock Exam 2
Multiple Choice
1. Aluminum (III) sulfite is an ionic compound. What is the correct way to represent
the formula of this compound?
a). AlSO3+
b). Al(SO3)2c). Al3+SO32d). Al2(SO3)3
e). Al7(SO3)11
2. VSEPR theory serves to do which of the following?
a). To minimize electron-pair collisions
b). To minimize electron-pair repulsions
c). To maximize electron-pair collisions
d). To maximize electron-pair repulsions
3. In the best possible Lewis structure for carbonic acid (H2CO3), which of the
following is true?
I.
The carbon is sp3 hybridized.
II.
Each of the oxygen atoms has tetrahedral electronic geometry.
III.
The orbitals that form the sigma bond between the O and H are 1s and sp3.
a). I only
b). II only
c). I and II only
d). III only
e). I, II, and III
4. The electronic and molecular geometries, respectively, for XeF4 are
a). trigonal bipyramidal, square planar
b). octahedral, square pyramidal
c). octahedral, square planar
d). tetrahedral, tetrahedral
5. What is the formal charge on the central atom in the best Lewis structure of ClO4-?
a). +3
b). +2
c). 0
d). -1
6. How many resonance structures are possible for the nitrite ion?
a). 1
b). 2
c). 3
d). 4
e). 5
CH 115 Fall 2014
Mock Exam 2
7. What is the predicted O-N-O bond angle in the nitrate ion?
a). 109.5o
b). 45o
c). 90o
d). 180o
e). 120o
8. Acetic acid, CH3COOH, has ____ sigma bonds and _____ pi bonds.
a). 1,7
b). 2,6
c). 6,2
d). 7,1
e). 8,0
9. Which of the following trends in electronegativity is correct?
a). B>C>N>O>F
b). F>Cl>Br>I>At
c). Tl>In>Ga>Al>B
d). Al>Si>P>S>Cl
10. In the compound CS2, the carbon-sulfur bonds are ____________ and the molecule has a
net _______ dipole moment.
a). Nonpolar, zero
b). Nonpolar, non-zero
c). Polar, zero
d). Polar, non-zero
11. Which of the following intermolecular interactions are present in CH3CN?
I.
London dispersion forces
II.
Dipole-dipole forces
III.
Hydrogen bonds
a). I only
b). II only
c). I and II only
d). I and III only
e). I, II, and III
12. How many atoms of carbon are there in 0.56 moles of ethanol (CH3CH2OH)? OMIT
a). 3.4 x 1023
b). 6.7 x 1023
c). 9.3 x 10-25
d). 1.9 x 1022
CH 115 Fall 2014
Mock Exam 2
13. For which of the following molecules/ions does the oxygen atom have the positive
end of the dipole moment?
a). H2O
b). NO2
c). OF2
d). OHShort Answer
14. Answer the following questions pertaining to the figure below. Lone pairs and all
carbon atoms may not be shown.
CH3
N
NH
NH
O
a). How many sigma bonds and pi bonds are present? 15 sigma, 2 pi
b). What is the hybridization and electronic geometry of the oxygen atom? Sp2,
trigonal planar
c). How many of the atoms in this molecule are sp2 hybridized? 4
15. Fill in the table below.
Name
Arsenic trichloride
Aluminum oxalate
2,3,6-trimethyloctane
Copper (II) nitride
CH3
H3 C
H3 C
What is the name of this
line structure?
4-ethylheptane
Formula
AsCl3
Al2(C2O4)3
C11H24
Cu3N2
C9H20
Ionic or Molecular?
molecular
Ionic
Molecular
Ionic
molecular
CH 115 Fall 2014
Mock Exam 2
16. Draw all the possible Lewis structures for each of the following molecules or ions.
Indicate the bond angles around the central atom and the formal charge of the
central atom for each structure.
a). H2SeO3 less than 109.50, formal charge = +1
b). SO42- 109.50, formal charge = +2