General Chemistry
Name:
Final Exam Review 2013
Chemical Formulas, Molar Mass, and Mole Conversions
# 1 – 8 Define the terms
1.
2.
3.
4.
atom
Avogadro’s constant
chemical formula
formula unit
5.
6.
7.
8.
molar mass
molar volume
molecule
subscript
9. List units for atomic mass, formula mass, and molar mass
10. Name all the elements that exist as diatomic molecules.
11. What can be said about the number of particles in 1 mol H2 and 1 mol Cu?
12. How many moles of nitrogen atoms are present in 4 moles of NH4NO3?
13. How many atoms of fluorine are in a molecule of carbon tetrafluoride (CF4)?
14. Determine the number of moles in 55 grams of Fe.
15. How many formula units are in 10 grams of AlCl3?
16. Determine the mass of 2.5 x 1024 molecules of C6H12O6.
17. Determine the number of formula units of 85 grams NaCl.
18. What is the molar mass of silver (Ag)?
19. What is the molar mass of (NH4)2SO4 ?
20. What is the mass of 2.5 moles of carbon?
21. You have 8.9 x 1024 molecules of oxygen gas, O2. What is the mass in grams of that number of
molecules?
22. What is the mass in grams of 2.29 moles of SO2 gas?
23. Determine the number of grams of methane CH4 if you are given 2.0 x 1024 molecules of methane.
24. Determine the volume (liters) occupied by 35.0 g of CO2 gas at STP.
25. What is the formula weight (molar mass) of ammonium carbonate (NH)2CO3?
26. A sample of silver nitrate (AgNO3) has 9.05 x 1024 formula units. How many grams of silver nitrate
are present?
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Empirical & molecular formulas/percent composition
#27 – 28 Define the terms
27. Empirical formula
28. Molecular formula
29. What is the empirical formula for a compound that is 43.6% phosphorus and 56.4% oxygen?
30. What is the percentage composition of CuCl2 ?
31. A compound contains 13.65 g of C and 36.35 g of O. What is the empirical formula for this
compound?
32. The percentage composition of sodium in NaBr is about 22.4%. What is the percentage of bromine
in this compound?
33. What is the percentage composition of chlorine in NaCl?
34. Find the empirical formula for a compound that is 46.8% iron, 17.3% phosphorus and 35.8% oxygen.
35. A molecular compound has the empirical formula X3Y2. Give examples of possible molecular
formulas.
36. A compound’s empirical formula is C3H3O. If the formula mass is 110 amu, what is the molecular
formula?
37. What is the empirical formula for C6H12O6.
38. A compound contains 11.19 g of H and 88.81 g of O. What is the empirical formula for this
compound?
39. A sample of a molecular compound was analyzed and found to contain 36.35 g carbon (C), 6.08 g
hydrogen (H) and 57.58 g fluorine (F). Determine the empirical formula of the compound.
40. Give the empirical formula for each of the following:
a. H2O2
d. Al2O3
b.
e.
P4O10
C6H12O6
c.
C6H12O3
41. A compound has the empirical formula C2H4O. Its molecular mass is found to be 132.16 g/mol.
What is this compound’s molecular formula?
42. Argentite is a silver ore that contains 87 g silver (Ag) and 13 g sulfur (S). What is the empirical
formula for argentite?
43. What is the percent composition of the compound carbon dioxide?
44. A sample weighing 88.0 grams contained 24.0 grams of carbon and 64 grams of oxygen. What is the
percent composition of this compound?
45. Calculate the percentage of aluminum in Al2O3.
2
Chemical Reactions, Reaction Types, and Balancing Equations
# 46 – 51 Define the terms
46. coefficients
47. limiting reactant
48. precipitate
49. product
50. reactant
51. spectator ions
52. What do the following symbols mean?
(g)
(l)
(s)
(aq)
53. List and define the five different classifications of chemical reactions and give the general form for
each.
54. When balancing a chemical equation, why must the formula subscripts remain unchanged?
55. Balance the following reactions and identify the reaction type.
a.
___ Ga(s) + ___ S(s) → ___ Ga2S3(s)
b.
___ S + ___O2 → ___ SO3
c.
___ C2H6 + ___ O2 → ___ CO2 + ___ H2O
d.
___ Fe3O4 + ___ Al → ___ Al2O3 + ___ Fe
e.
___ Na + ___ I2 → ___ NaI
f. Fe3N2 + Al → AlN + Fe
g. Zn(OH)2 + CH3COOH →
Zn(CH3COO)2+
H2 O
h. KClO3(s) → KCl(s) + O2(g)
i. NH4NO2 →
N2 +
H2 O
j. ___ C3H8(g) + ___ O2(g) → ___ CO2(g) + ___ H2O(l)
56. List all the changes that indicate that a chemical reaction has occurred.
57. When a glass blower shapes molten glass into an ornament, does a chemical reaction occur? Explain.
3
Stoichiometry
# 58 – 59 Define the terms
58. law of conservation of mass
59. stoichiometry
60. The ratio of chlorine to hydrogen chloride in the reaction H2(g) + Cl2(g) → 2HCl(g) is
Use the following equation to answer questions 61 & 62.
H2SO4 + 2NaOH → 2H2O + Na2SO4
61. If 10 moles of H2SO4 were available, how many moles of NaOH would be needed for the sulfuric
acid to react completely?
62. How many moles of Na2SO4 could theoretically be produced if there were 6 moles of H2SO4
available?
63. For the balanced equation, 3 CaCO3 + 2 H3PO4 → Ca3(PO4)2 + 3 H2CO3, if you need 3 mol of
Ca3(PO4)2, how many moles of each reactant should you start with?
64. In the reaction 2 H2O + O2 → 2 H2O2, what is the mole ratio of water to oxygen?
65. In the reaction Ca + Cl2 → CaCl2, what is the mole ratio of chlorine to calcium chloride?
66. What mole ratio would you use if you were given the number of moles of oxygen (O2) to and needed
to find the number of moles of hydrogen peroxide (H2O2) in the following reaction?
2 H2O2(l) → 2 H2O(l) + O2(g)
67. The reaction of tin and chlorine is,
Sn(s) + 2Cl2(g) → SnCl4(l)
If you have 8 moles of Sn; how many moles of chlorine do you need?
68. What mass in grams of C3H7Cl is produced if 400.g of propane C3H8 reacts with chlorine gas
according to the equation?
C3H8 + Cl2 → C3H7Cl + HCl
69. What volume in liters of H2 is produced if 20.0 g of sodium metal reacts with excess water according
to the chemical equation
2 Na(s) + 2 H2O(l) → 2 NaOH(aq) + H2(g)
4
Gas Behavior and Gas Laws
# 70 – 75 Define each gas law and write down the formula:
70. Boyle’s Law
71. Charles’s Law
72. Combined Gas Law
73. Dalton’s Law
74. Gay-Lussac’s Law
75. Ideal Gas Law
76. What formula is used to convert from °C to K and what formula is used to go back from K to °C?
77. Standard temperature and pressure (STP) for a gas is
78. A sample of a gas has a volume of 250 mL when its pressure is 0.487 atm. What will the volume of
the gas be at a pressure of 0.789 atm, if the temperature remains constant?
79. A sample of a gas has a pressure of 2.00 atm at 28°C. What would the gas pressure be at 72°C, if the
volume remains constant?
80. What are all of the points of the Kinetic Molecular Theory?
81. What happens to the volume of a gas during compression?
82. Calculate the approximate volume of a 0.600 mol sample of gas at 15.0°C and a pressure of 1.10 atm.
83. A sample of oxygen occupies 20.0 L under a pressure of 115 kPa. At what pressure will it occupy
15.6 L if the temperature does not change?
84. If the gas occupies 50.0 mL at a temperature of 253 K, what is the volume of a gas at 273 K?
85. How many mol of N2 gas can occupy a 10 L container at a pressure of 1823 kPa and a temperature of
423 K? (R = 8.314 L kPa/mole K)
86. The volume of a gas is 50.0 mL under a pressure of 97.3 kPa and at a temperature of 297 K. What
would the volume be if it were measured under 95.7 kPa and at 286K?
States of Matter / Thermochemistry
# 87 – 108 Define the terms
87. absolute zero
88. allotrope
89. amorphous
90. barometer
91. condensation
92. endothermic
93. enthalpy
94. evaporation
95. exothermic
96. heat
97. heat capacity
98. kinetic energy
99. melting
100.
molar heat of fusion
101.
molar heat of vaporization
102.
phase diagram
103.
pressure
104.
sublimation
105.
temperature
106.
thermochemistry
107.
unit cell
108.
volume
5
109.
List various units used when measuring pressure, temperature, volume, and heat. Underline
the ones that are the SI units.
110.
Nonspontaneous reactions can occur when
Solutions / Acids and Bases
# 111 – 131 Define the terms
111.
112.
113.
114.
115.
116.
117.
118.
119.
120.
121.
acid-base reaction
alloy
amphoteric
aqueous solution
Arrhenius acid
Arrhenius base
Bronsted-Lowry acid
Bronsted-Lowry base
dessicant
electrolytes
hydrogen bonding
122.
123.
124.
125.
126.
127.
128.
129.
130.
131.
132.
In the expression “like dissolves like”, the word “like” refers to similarity in molecular
133.
Acids taste
134.
Acids make pH paper turn
135.
Pure water contains
136.
The pH scale in general uses a range from
137.
The pH of a basic solution is
138.
A water solution whose pH is 4 is said to be what?
139.
Identify dyes with pH-sensitive colors
140.
Contrast Brønsted-Lowry Acids and Bases and Arrhenius Acids and Bases.
6
immiscible
ions
molality
molarity
solubility
solute
solution
solvent
supersaturated solution
suspension