CHEM 101
Test 2-A
Ms. A. Dupre
Fall 2003
Name:
SSN:
Multiple Choice: (60 pts total; 3 pts each) Choose the correct answer for each of the following
questions. Write the letter clearly in the blank next to the numbers.
_____1.
An element or ion that satisfies the octet rule possesses how many valence
electrons?
a. 2
b. 6
c. 8
d. 14
_____2.
In order to satisfy the octet rule, elements in Group IIIA will
a. gain 3 electrons
b. lose 3 electrons
c. lose 5 electrons
d. gain 5 electrons
_____3.
Which of the following chemical formulas is the correct formula for potassium sulfate?
a. PSO4
b. K(SO4)2
c. PSO3
d. K2SO4
_____4.
In the Lewis dot structure of CO2, how many unshared pairs of electrons does each oxygen
atom possess?
a. 5
b. 2
c. 3
d. 1
_____5.
Which of the following elements would be considered the most electronegative?
a. B
b. Be
c. Mg
d. O
_____6.
Which of the following is the correct order of reactivity for the elements lithium,
aluminum, calcium, and rubidium? Elements are listed from most reactive to least
reactive.
a. Rb, Li, C, Al
b. Li, Al, Ca, Rb
c. Rb, Ca, Al, Li
d. Rb, Al, Ca, Li
_____7.
Which of the following molecules is polar?
a. NCl3
b. CO2
c. O2
d. CCl4
What do we expect to be the geometry of a molecule of NCl3?
a. bent
b. pyramidal
c. tetrahedral
d. linear
_____8.
_____9.
The symbol,
→
, in an equation implies that
a. The reaction is reversible
c. The reaction will not occur
_____10.
b. the reaction is irreversible
d. the reaction has not begun
In order to balance the following chemical equation, the coefficient in front of the
water must be:
Na3P + H2O 
NaOH + PH3
a. 12
b. 2
c. 3
d. 6
_____11.
Which of the following is considered the strongest intermolecular force?
a. dipole interaction
c. all forces have equal strength
b. hydrogen bonding
d. ionic interaction
_____12.
Which one of the following properties of water is incorrect?
a. water is a liquid at room temperature
b. water has a high surface tension
c. water is a poor solvent
d. water molecules exhibit hydrogen bonding capabilities
_____13.
According to the naming rules for ionic compounds, what is the correct name for the
molecule CoCl3?
a. cobalt (II) chloride
b. cobalt (III) chloride
c. cobalt trichloride
d. cobalt chlorate
_____14.
What is the mass of 1 mole of a compound called?
a. molar mass b. electronegativity c. Avagadro’s number d. atomic number
_____15.
In a triple covalent bond, how many electrons are being shared by the two atoms?
a. 2
b. 3
c. 12
d. 6
_____16.
What is represented by 1 mole?
a. 1 g of a substance
c. a burrowing animal
b. 6.02 x 1023 molecules
d. a dozen eggs
_____17.
How many atoms of sulfur are there in 0.0554 mol of iron?
a. 3.33 x 1022 atoms
b. 7.06 x 1023 atoms
c. 9.90 x 1022 atoms
d. 5.65 x 1024 atoms
_____18.
What is the molar mass of nicotine C10H14N2?
a. 412.4 g/mol
b. 27.03 g/mol
c. 162.2 g/mol
d. 148.2 g/mol
_____19.
Which of the following bonds is considered the most polar?
a. C-O
b. C-H
c. C-N
_____20.
d. C-C
Boron trifluoride reacts with water to produce two products, H3BO3 and HBF4. Which of
the following equations correctly represents this reaction?
a. 3BF4 + 3H2O  H3BO3 + HBF4
b. 2BF3 + 2H2O  2H3BO3 + HBF4
c. 4BrF3 + 3H2O  H3BrO3 + 3HBrF4
d. 4BF3 + 3H2O  H3BO3 + 3HBF4
Short Answers: (40pts)
Provide the correct answer to each of the following questions. Partial credit will be awarded, so show all
of your work.
1.
2.
Give the correct name for the following compounds (6pts):
a.
(NH4)2SO4
b.
SF6
Identify the following compound names by writing the correct chemical formula for the following:
(6pts)
a.
gallium hydroxide
b.
3.
4.
potassium phosphate
Consider the molecule H2S (6 pts.)
a.
Write the Lewis dot structure for this molecule.
b.
Predict its geometry.
c.
Determine if the molecule is polar or nonpolar.
Perform the following conversions and calculations. Be sure to report your answers in the correct
number of significant figures. (6pts)
a.
12.5 kg = _____________g
b.
11 mL = ______________kL
c.
(2.99718 + 3.4452) x 1425.879362 = ____________________
5.
Consider the following reaction: (6pts.)
HCl (aq)
Al(OH)3 (s)

AlCl3 (aq)
+
H2O(l)
a.
Balance this reaction
b.
Using the balanced equation, what mass in grams of HCl is needed to produce 1.00 mole of
AlCl3?
c.
How many molecules are there in 3 moles of HCl?
A catalyst is added to the reaction described by the energy diagram below. On the diagram, draw a
line indicating the reaction path after the addition of the catalyst (2 pts.).
Energy
6.
+
Reactant
s
Product
Progress of Reaction
7.
According to Le Chatelier’s principle, what direction (to the right or to the left) will the following
equilibrium shift to if the size of the container is decreased? (2pts.)
2 NH3 (g)
8.
N2 (g) + 3H2 (g)
In the following pairs of molecules, which is expected to have the higher melting/boiling point?
Indicate your answer by drawing a circle around the appropriate molecule. (6 pts.)
a. NH4NO3
vs.
MgSO4
b. O2
vs.
H2O