Name________________________________________________
AP Chemistry final exam review Packet
Tuesday, June 16, 2015
ROOM ______________________
EXAM FORMAT
The exam will be 100 points:
Part I
Multiple Choice Questions
50 @ 1 point each
Part II
Problems
50 points total
You will be provided with an AP Chemistry I reference booklet.
REVIEW
A review packet which covers important concepts from this past semester is attached.
Use your notes, homework, quizzes and labs as study aids. The end of each chapter in
the book also contains a good summary of important conceptual items and formulas.
AP Chemistry I Review Packet 2015
Molecular Geometry
I. Fill in the following table:
Lewis dot structure
3-D shape (name of
geometry)
Polar or
nonpolar?
Hybridization
on central atom
1. SiH3-1
2. BF3
3. CHCl3
4. XeF4
5. SF3-1
II. Count the number of sigma and pi bonds in the following molecule:
CH3CH2COOH
# sigma__________#pi_________
2
Gases
I. Assorted Problems
A. What is the volume occupied by 4.50 g of nitrogen gas at STP? How many molecules in this
sample?
B. What mass of CH4 can be contained in a 350 mL flask at 650 mm Hg and –50. degrees C?
C. Put the following gases in order from the one with the highest average speed (rms speed) to
the one with the lowest average speed. How does this relate to the order of diffusion (effusion)?
SO2
He
N2
O2
D. Put the same four gases in order of density, if all are measured at the same T and P.
E. Put the same four gases in the order of volume of 1 mole of each gas at STP.
F. Suppose you mix together 14.0 g of nitrogen, 4.0 g of oxygen, and 33.0 g of carbon dioxide
gas in a container. If the total pressure of the mixture is 750.0 mm Hg, what is the partial
pressure of each gas?
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G.
i) A 120. mL flask contains 0.345 g of a gaseous substance at 100. degrees C and 760. mm Hg.
What is the molar mass of the substance?
ii) If the unknown substance from Part i) above has the following % composition, what is its
molecular formula?
54.5 % Carbon
36. 4% Oxygen
4
9.10 % Hydrogen
II. Gas Laws and Stoichiometry
A. Write the balanced equation for the reaction of magnesium metal with hydrochloric acid.
B. What volume of hydrogen gas measured at 1.50 atm and 80.0 degrees C will be generated if
500. mL of 0.350 M hydrochloric acid is reacted with an excess of magnesium?
C. You are given 1.56 g of a mixture of KClO3 and KCl. When heated, the KClO3 decomposes
to KCl and O2.
a. Write the balanced equation.
b. If 327 mL of O2 with a pressure of 735 mm Hg is collected at 19 deg. C, what is the weight
percentage of KClO3 in the sample?
III. Real vs. Ideal Gases
A. Under what conditions do real gases approximate ideal behavior? Why?
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Properties of Liquids & Solids
I. Types of Intermolecular Forces
A. For each of the substances below, list the main IMF. Rank the list in terms of boiling point.
BH3
CBr4
CH3OH
HF
PCl3
C6H6(benzene)
B. For each of the substances in Part A, describe their solubility in water and how the IMF
impacts this property.
C. Distinguish between ionic, molecular, network covalent and metallic solids using their
properties.
II. Phase Diagrams, Vapor Pressure Curves, and Boiling
A. Explain how atmospheric pressure influences boiling point.
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B. Explain how to use a vapor pressure curve to determine normal boiling point and rank
volatility.
C. Draw a phase diagram for water and label the following: triple point, critical point, normal
boiling point, normal melting point. Also label the solid, liquid and gas regions; and the fusion,
vapor phase and sublimation curve. Discuss the significance of the slope of the fusion curve.
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Solutions
I. Concentration Units
A. Describe how each of the following units of solution concentration are calculated.
ppm
weight (mass) percent
molality
molarity
B. An aqueous solution of ethylene glycol is 40.0% HOCH2CH2OH by mass and has a density
of 1.05 g/mL. What is the molarity, molality, and mole fraction of HOCH2CH2OH in the
sample?
C. Explain how to determine if a solution is saturated, supersaturated or unsaturated using a
solubility graph or curve.
II. Colligative Properties
A. Rank the following in terms of boiling point and explain your rankings: pure water, 1.0 M
glucose, 1.0 M NaCl, and 1.0 M MgCl2.
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B. A student wishes to determine the molar mass of an unknown substance. He dissolves 29.5 g
of the substance in 692.4 mL of a solvent. The solvent has a normal boiling point of 45.0 degrees
C, a kb of 2.80 degrees/m, and a density of 1.30 g/mL. The resulting solution boils at 46.0
degrees C. What is the molar mass of this unknown?
3. If the unknown substance from Part 2 above has the following % composition, what is
its molecular formula?
52.35% Carbon
34.50% Oxygen
9
13.09% Hydrogen
Rates
I. Rate Laws and Mechanisms
A. Consider the following data for the reaction below:
2A
+

B
3C
[A], M
[B], M
Rate, M/sec
0.100
0.300
2.50 x 10-3
0.300
0.300
2.25 x 10-2
0.300
0.600
2.25 x 10-2
Determine the rate law (expression) and the value of k (including units) for the above reaction.
B. Which of the following mechanisms is consistent with the rate law? Explain your answer by
deriving the rate law from the mechanism.
i)
ii)
iii)
A

Q
(fast)
A
+
Q

D
(slow)
D
+
B

3C
(fast)
A
+
B

Q
(fast)
A
+
Q

D
(slow)
D
+
B

3C
(fast)
A
+
A
B

Q
(slow)

3C
(fast)
+
Q
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II. Potential Energy Diagrams
A. Define the following:
a. Intermediate:
b. Catalyst:
c. Rate determining step:
d. Reaction mechanism:
e. Activation energy:
B. Sketch an energy diagram for a reaction with:
- potential energy of the reactants of 40 kJ
- activation energy of 80 kJ
- heat of the reaction of -20 kJ
- activation energy with a catalyst of 60 kJ
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Equilibrium
I. Write a balanced equation for the decomposition of 2 moles of HCl (g) to its elements.
II. Write the equilibrium expression for the above equation.
III. A student measures the following concentrations for the above reaction:
[Cl2] (initial) =
[H2]
(initial)
0.625 M
=
0.170 M
[HCl] (equilibrium) =
0.250 M
If there was no HCl present initially in the flask, what is the value of Kc for this reaction?
IV. What is the value of Kc for the synthesis of 4 moles of HCl from its elements?
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V. For the same decomposition of HCl in a 2.00 L flask, another student measures the following
initial values:
Moles of Cl2 (initial)
=
1.000
Moles of H2
=
1.000
(initial)
Using the same equilibrium constant that you found in Part III, calculate the equilibrium
concentrations of all the substances in the reaction.
VI. For the following reaction, explain how the yield (quantity) of NO2 can be increased at
equilibrium.
2NO (g) +
O2(g)  2NO2 (g)
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ΔH = negative
Acids and Bases
1. Write the dissociation equation and calculate the pH, pOH, [H+], and [OH-] for the following:
a. 0.10 M HCl
b. 0.1 M Ba(OH)2
c. 0.10 M HCN:
Ka = 6.2 x 10-10
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d. Write the equation for the interaction of HCN with water, and identify the Bronsted-Lowry
acid, base, conjugate acid and conjugate base.
2. A 0.100 M solution of an unknown monoprotic acid is prepared. The pH of this solution is
measured at 2.43. What is the Ka of the acid?
3. 0.100 M HCl is titrated with 450.0 mL of 0.300 M Sr(OH)2 to reach the equivalence point.
a. Write the net ionic equation for the neutralization reaction.
b. Calculate the amount of acid needed for the titration.
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