Chemistry 106: General Chemistry
Syracuse University Project Advance
Exam #3, Fall 2013
Name
Date
The last page of the examination are reference tables.
(1).
All of the following about resonance are true except
a)
b)
c)
d)
e)
(2).
How many electrons are shown in the Lewis formula for the chlorate ion, ClO3-?
a)
b)
c)
d)
e)
(3).
resonance describes a more stable situation than does any one contributing
resonance formula.
a single Lewis formula does not provide an adequate representation of the bonding.
resonance describes the bonding as intermediate between the contributing resonance
formulas.
resonance describes the oscillation and vibration of electrons.
the contributing resonance formulas differ only in the arrangement of the electrons.
24
26
28
30
32
The formal charge on the sulfur atom in sulfur trioxide, SO3, is
a)
b)
c)
d)
e)
-2
0
+2
+4
+6
(4).
In ClF3, the electron pairs are arranged about the chlorine atom in
a)
b)
c)
d)
e)
(5).
Which of the following does not describe a covalent bond?
a)
b)
c)
d)
e)
(6).
an octahedron
a trigonal pyramid
a trigonal bipyramid
a square plane
a tetrahedron
electrons are attracted simultaneously to both positive nuclei forming the bond.
involves overlapping orbitals of the atoms that compose it.
sharing of core (inner) electrons.
all describe covalent bonds.
none describe covalent bonds.
Which of the following molecules has/have sp3 hybrid orbitals on the central atoms(s)?
I. CH4
II. BF3
III. H2O
IV. H2C=CH2
V. NH3
a)
b)
c)
d)
e)
(7).
II and IV
I and III
I, II and V
I, II, and III
I, III, and V
In ketene, H2CCO, the atoms are bonded in the order shown, with both hydrogens bonded
to the leftmost carbon. The bonding in ketene is best described as
a)
b)
c)
d)
e)
four  bonds and one  bond.
five  bonds.
five  bonds.
four  bonds and two  bond.
three  bonds and two  bond.
C=C=O
(8).
A bond in which an electron pair is unequally shared by two atoms is
a)
b)
c)
d)
e)
(9).
The hybridization of the central atom in a molecule is described as sp2. The arrangement
in space of the hybrid orbitals about that atom is
a)
b)
c)
d)
e)
(10).
ionic.
coordinate covalent.
nonpolar covalent.
polar covalent.
dipolar.
tetrahedral
trigonal planar
trigonal bipyramidal
octahedral
linear
A  (pi) bond is the result of the
a)
b)
c)
d)
e)
sideways overlap of two parallel p orbitals.
overlap of two p orbitals along their axes.
overlap of two s orbitals.
sidewise overlap of two s orbitals.
overlap of an s orbital and a p orbital.
(11). Which of the following atoms in its ground state is diamagnetic?
a)
b)
c)
d)
e)
(12).
N
F
Ca
B
Si
A pair of atoms that are most likely to form covalent compounds are
a)
b)
c)
d)
e)
H and He
Na and F
H and Cl
Li and F
Na and Cl
(13).
Using molecular orbital theory, predict the bond order of the He2+ molecule.
a)
b)
c)
d)
e)
(14).
The molecule of propenol has the bond structure at right. The hybridization on the
three carbons, from right to left, is
a)
b)
c)
d)
e)
(15).
½
1
0
3
¼
sp3, sp3, sp
sp2, sp2, sp3
sp, sp2, sp3
sp2, sp, sp3
sp2, sp3, sp3
H
H
H–C–C=C–O-H
H
H
The order of filling of molecular orbitals in homonuclear diatomics is as follows:
1s < *1s < 2s < *2s < 2p < 2p < *2p < *2p
The molecule of C2 has 12 electrons. The bond orders in C2 and in the anion C2- are
a)
b)
c)
d)
e)
1 and 2
1 and 3/2
2 and 3/2
2 and 5/2
2 and 3
(16). A mixture of two gases, A and B, at a total pressure of 0.95 atm is found to contain 0.32
moles of gas A and 0.56 moles of gas B. What is the partial pressure (in atm) of gas B?
a)
b)
c)
d)
e)
1.7
1.5
0.6
0.35
1.2
(17).
Ammonium sulfate is produced by reacting ammonia with sulfuric acid, according to:
2NH3(g) + H2SO4(aq)  (NH4)2SO4(aq). What volume of ammonia gas at 15°C and
1.15 atm is required to produce 1.136 mol of ammonium sulfate?
a)
b)
c)
d)
e)
11.7 L
20.5 L
23.4 L
40.6 L
46.7 L
(18). If a certain number of moles of a gas occupies a volume of 200 mL at 25°, what volume
would it occupy if it was heated to 40°C at a constant pressure?
a)
b)
c)
d)
e)
210 mL
320 mL
230 mL
500 mL
120 mL
(19). The density of a gas is 3.48 g/L at STP. What is its molecular weight?
a)
b)
c)
d)
e)
(20).
44.6 g/mol
224 g/mol
78.0 g/mol
32/mol
147 g/mol
What is the partial pressure of oxygen in a container that contains 2.0 mol of oxygen, 3.0
mol of nitrogen, and 1.0 mol of carbon dioxide when the total pressure is 900 mmHg?
a)
b)
c)
d)
e)
150 mmHg
200 mmHg
300 mmHg
450 mmHg
600 mmHg
(21).
A flask of volume (total volume) 1.00 L contains 8 g of O2 and 3 g of He at 0°C.
Calculate the total pressure. [Molar masses: O2 = 32.0 g/mol; He = 4.00 g/mol; He =
4.00 g/mol; R = 0.08206 L atm mol-1 K-1].
a)
b)
c)
d)
e)
(22).
0.5 atm
1 atm
2.24 atm
22.4 atm
24.6 atm
Propane, C3H8, has a molar mass of 44.1 g/mol. The total mass of propane in a 20 L tank
pressurized at 100 atm and 0°C is
a)
b)
c)
d)
e)
0.394 g
39.4 g
0.254 kg
0.3932 kg
3.932 kg
(23). A tank of volume 40 L contains a gas at 1.0 atm pressure and a temperature of 20°C.
Another tank, of volume 10 L, contains the same gas, also at 20°C, but at 6.0 atm pressure.
The tanks are connected so gas can flow between them, with the temperature maintained at
20°C. At equilibrium, the pressure is the same everywhere in the total volume of 50L. What
is the final pressure?
a)
b)
c.)
d)
e)
1.4 atm
1.5 atm
1.6 atm
2.0 atm
3.0 atm
(24).
Here are three possible statements about the molecules in a gas:
I. Even if there is a mixture of different types of gas molecules, the different types will all
have the same average speed.
II. The amount of space (volume) occupied by the gas molecules themselves is negligible
compared to the volume of empty space between the molecules.
III. The attractive forces between gas molecules is negligible.
Which of these statements are true, according to the kinetic-molecular theory of the ideal
gas?
a)
b)
c)
d)
e)
(25)
none of them
I and II
II and III
I and III
all of them
A mixture of 0.924 g of N2O and 0.825 g of NO exerts a pressure on a container of 1.32
atm. The partial pressure of each gas is
a)
b)
c)
d)
e)
N2O = 1.32 atm and NO = 1.32 atm
N2O = 0.70 atm and NO = 0.62 atm
N2O = 0.57 atm and NO = 0.75 atm
N2O = 0.66 atm and NO = 0.66 atm
N2O = 0.78 atm and NO = 0.54 atm
(EC). An empty 2.0 L soda bottle is tightly capped with 2g of N2 inside. If the bottle is placed
in water at 95°C, what is the pressure in the bottle in mmHg? (SHOW ALL WORK)