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Chemistry Semester Exam Review
Complete all problems on notebook paper. Transfer your final answers to the answer sheet.
Measurements and Calculations
Significant Figures – adding, subtracting, multiplying, dividing
Scientific Notation - adding, subtracting, multiplying, dividing
Metric Conversions
Dimensional Analysis
Temperature Conversions
Density – D=m/V, V=LWH, V=r2h, V=Vf - Vi
Determine the number of significant figures in the following numbers.
a. 1 SF
b. 2 SF
c. 4 SF
d. 6 SF
e. 10 SF
1. 0.0000787690 g d
2. 900000 km a
3. 0.009001 mm c
4. 9.100 cg c
Record your answer with the correct number of significant figures and units.
5. 45.6 g + 3.59 g
a. 49.19 g
b. 49.0 g
c. 49.2 g
d. 49.20 g
6. 0.00134 mL - 0.00023 mL
a. 0.00111 mL
b. 11 mL
c. 0.0011 mL
7. (56.2 cm)(1.234 cm)
a. 69.3 cm2
b. 69.4 cm2
c. 69.3508 cm2 d. 69.35 cm2
8. (3.20 km2)/(4.0 km)
a. 13 km
b. 8 km
c. 0.80 km
d. 0.00157 mL
d. 2.56 km
Convert the following numbers from scientific notation to ordinary notation.
9. 3.02 x 10-3 g
a. .302 x 10-3 g
b. 3.02 g
c. 0.00302 g
d. 3020 g
10.
5.791 x 105 m
a. 579100 m
b. 5.791 m
c. 0.00005791 m d. 57910 m
Convert the following numbers from ordinary notation to scientific notation.
11. 4560 cm
a. 456 x 103 cm b. 4.56 x 103 cm c. 4.56 x 10-3 cm d. 4.56 cm
12. 0.0076 g
a. 7.6 x 10-3 g
b. 7.6 x 103 g
c. 76 x 10-3 g d. 0.0076 x 10-3 g
Perform the following calculations.
13. How many kilograms are in 234 mg?
a. 234000 kg
b. 234 kg
c. 0.000234 kg
14. How many micrometers are in 0.000325 km?
a. 325 μm b. 325000 μm
c. 0.325 μm
d. 0.234 kg
d. 0.000325 μm
15. The Density of Mercury is 13.0 g/mL. If you have 24.3 mL of Mercury,
how much does it weigh?
a. 316 g
b. 315.9 g
c. 0.535 g
d. 1.87 g
16. A cube of wood that weighs 16.5 g measures 24.21 cm by 1.45 cm by
7.34 cm. What is the density of the wood?
a. 7.25 g/cm3 b. 0.0640 g/cm3 c. 258 g/cm3
d. 4250 g/cm3
Matter
Chemical vs. Physical Properties
Chemical vs. Physical Changes
Elements and Compounds
Mixtures and Solutions
Classify the following as a) chemical property or b) physical property.
17. Color b) physical property
18. Flammability a) chemical property
19. Solubility b) physical property
Classify the following as a) chemical change or b) physical change.
20. tearing paper b) physical change
21. burning wood a) chemical change
22. boiling water b) physical change
Classify the following as an a) element or a b) compound.
23. Phosphorus a) element
24. carbon dioxide b) compound
25. water b) compound
Classify the following as a) mixture or b) pure substance.
26. a multivitamin tablet a) mixture
27. distilled water b) pure substance
28. tap water a) mixture
Classify the following as a) homogeneous mixture or b) heterogeneous mixture.
29. chunky peanut butter b) heterogeneous mixture
30. a solution of copper (II) sulfate a) homogeneous mixture
31. a bag of trail mix b) heterogeneous mixture
Chemical Foundations: Elements, Atoms, and Ions
Dalton’s Atomic Theory
Subatomic Particles – Protons, Neutrons, Electrons
History of the Atom
Isotopes
Atomic Numbers and Mass Numbers
Cation vs. Anion
Ratio of Atoms
Nuclear chemistry
Give the symbols for the following elements
a. B
b. Be
c. H
32. Beryllium b. Be
33. Boron a. B
34. Helium d. He
35. Hydrogen c. H
d. He
Write the formula for the compound containing
36. a two to three ratio of iron to oxygen
a. Fe2O3
b. I2O3
c. Fe3O2
d. I3O2
37. six carbon, twelve hydrogen and six oxygen
a. CH2O
b. C6H12O6
c. C6H6O6
Name the scientist responsible for the following. Put in order (c, b, a)
a. Gold Foil Experiment
b. Plum Pudding Model c. Atomic Theory
38. John Dalton c. Atomic Theory (Solid Sphere Model)
39. Ernest Rutherford a. Gold Foil Experiment
40. JJ Thomson b. plum pudding model
Determine the number of protons, neutrons, and electrons in the following.
41. 41Ca
a. 41p, 41n, 41e
b. 20p, 20n, 20e
c. 20p, 41n, 20e
d. 20p, 21n, 20e
42. 60Co+3
a. 27p, 60n, 27e
b. 27p, 33n, 24e
c. 24p, 41n, 27e
43. 6Li+1
a. 6p, 6n, 7e
b. 3p, 3n, 3e
c. 3p, 3n, 2e
44. 31P-3
a. 15p, 31n, 15e
b. 15p, 16n, 15e
c. 15p, 16n, 18e
d. 27p, 33n, 30e
d. 6p, 2n, 3e
d. 31p, 15n, 17e
Complete the following nuclear equations by supplying the missing particle. Classify the
type of decay
4
a. 2 He , alpha decay b.
4
2
He , beta decay c.
0
1
e , alpha decay d.
45.
226
88
Ra 
222
86
Rn + _?_
a. 2 He , alpha decay
46.
222
86
Rn 
218
84
Po + _?_
a. 2 He , alpha decay
47.
39
17
48.
23
10
4
d.
Ne 
d.
Na + _?_
e , beta decay
4
Cl  39
18 Ar + _?_
23
11
0
1
0
1
e , beta decay
0
1
e , beta decay
Average Atomic Mass
Average Atomic Mass - the weighted average of the masses of the isotopes of
the element.
Average Atomic Mass = [(isotope mass)(percent abundance)]
To solve for percent abundance assign the first isotope x and the second isotope equal
to 100% - x.
49. There are two naturally occurring isotopes of rubidium: 85Rb, which has a
mass of 84.91 amu and 87Rb, which has a mass of 86.92 amu. The atomic
mass of rubidium is 85.47 amu. What is the percent abundance of each
of the isotopes?
85
a. Rb = 72.1 %, 87Rb = 27.9% c. 85Rb = 27.9%, 87Rb = 72.1%
b. 85Rb = 85%, 87Rb = 15%
d. 85Rb = 97.7%, 87Rb = 2.3%
85.47 amu * 100% = (84.91 amu * x) + [86.92 amu * (100% - x)]
8547 amu% = 84.91amu*x + 8692 amu% - 86.92amu*x
-145 amu% = -2.01amu*x
x = 72.1% 85Rb
100 – 72.1% = 27.9% 87Rb
50. If element X consists of 78.8% of atoms with a mass of 24.0 amu, 10.1%
of atoms with a mass of 25.0 amu, and 11.2% of the atoms with a mass
of 26.0 amu, what is the atomic mass of element X?
a. 25.0 amu
b. 24.3 amu
c. 33.3 amu
d. 2434 amu
x * 100% = (24.0amu*78.8%) + (25.0amu*10.1%) + (26.0amu*11.2%)
x*100% = 1890 amu% + 253 amu% + 291 amu%
x*100% = 2430 amu%
x = 24.3 amu
Semester Exam Review Part 2
Complete all problems on notebook paper. Transfer your final answers to the answer sheet.
Nomenclature
Periodic Table
Naming Compounds
Ionic, Molecular, Acids
Writing Formulas for Compounds
Ionic, Molecular, Acids
51. Write the name for the following compounds.
a. AuBr3 gold (III) bromide
g. Ag2SO4 silver sulfate
b. Co(CN)3 cobalt (III) cyanide
h. H2S hydrosulfuric acid
c. HNO2 nitrous acid
i. Be(OH)2 beryllium hydoxide
d. Mg3(PO4)2 magnesium phosphate
j. SF6 sulfur hexafluoride
e. HCN hydrocyanic acid
k. CuO copper (II) oxide
f. B2H6 diboron hexahydride
52. Write the formula for the following compounds.
a. barium peroxide BaO2
g. tricarbon hexahydride C3H6
b. tetraphosphorus decoxide P4O10
h. hydronitric acid H3N
c. cesium sulfite Cs2SO3
i. zinc nitrate Zn(NO3)2
d. manganese (II) acetate Mn(C2H3O2)2
j. cobalt (III) hydroxide Co(OH)3
e. sodium hypochlorite NaClO
k. pentanitrogen octoxide N5O8
f. nitric acid HNO3
Modern Atomic Theory
atomic theory
electron configuration
orbital diagram
periodic table trends
Ionization energy
Electron affinity
Atomic radius
electronegativity
53. Name the element that corresponds to each of the following electron
configurations.
a. 1s22s22p2 carbon
b. 1s22s22p63s23p4 sulfur
c. 1s22s22p63s23p64s23d5 Mn
d. 1s22s22p6 Ne
54. Write the electron configurations for the following elements.
a. Potassium 1s22s22p63s23p64s1
b. Barium 1s22s22p63s23p64s23d104p65s24d105p66s2
55. Write the orbital diagram for the following elements.
a. Bromine
1s  2s 2p    3s  3p    4s  3d     4p   
b. iron
1s  2s 2p    3s  3p    4s  3d    
56. Arrange the following elements in order of increasing atomic radius.
a. Cl, Mg, P, Na, Al
Cl, P, Al, Mg, Na
b. Rb, Na, Cs, Li, K
Li, Na, K, Rb, Cs
57. Arrange the following elements in order of increasing ionization energy.
a. Cl, Mg, P, Na, Al
Na, Mg, Al, P, Cl
b. Rb, Na, Cs, Li, K
Cs, Rb, K, Na, Li
58. Arrange the following elements in order of increasing electron affinity.
a. Cl, Mg, P, Na, Al
Na, Mg, Al, P, Cl
b. Rb, Na, Cs, Li, K
Cs, Rb, K, Na, Li
59. Arrange the following elements in order of increasing electronegativity
a.
Cl, Mg, P, Na, Al
Na, Mg, Al, P, Cl
b.
Rb, Na, Cs, Li, K
Cs, Rb, K, Na, Li
Chemical Bonding
Lewis structures
VSEPR
Linear
Bent
Trigonal planar
Trigonal pyramid
tetrahedral
polarity
60. Draw Lewis structures for the following:
Si
a.
b.
Silicon
Potassium phosphide
-3
K
+K
+ K
+
P
 3 K+
P
c.
Nitrogen triiodide
I
N
I
I
61. Predict the shape and polarity of the following molecules
a.
SiS2 linear, non-polar
b.
OBr2 bent, polar
c.
COCl2 trigonal planar, polar (because of O)
d.
PH3 trigonal pyramid, polar
e.
CF4 tetrahedral, non-polar
Chemical Composition
Moles
Avogadro’s Number
Molar Mass
Percent Composition
Empirical Formula
Molecular Formula
62. Calculate the molar mass of magnesium phosphate. Mg3(PO4)2
24.3 (3) + 31.0 (2) + 16.0 (8) = 262.9 g/mol
63. How many moles are in 7.23 grams of strontium oxide? SrO
7.23gSrO x 1 mol SrO = 0.0698 mol SrO
103.6g SrO
64. How many moles are in 3.02 x 1023 atoms of zinc?
3.02E23 atoms Zn x
1 mol Zn
= 0.502 mol Zn
6.02E23 atoms Zn
65. How many grams are in 7.2 x 1046 molecules of copper (II) sulfate?
7.2E46 molec CuSO4 x 1 mol CuSO4 x 159.6g CuSO4 = 1.9x1025g CuSO4
6.02E23 molec
1 mol CuSO4
66. How many grams are in 1.00 moles of sodium oxalate?
1.00 mol Na2C2O4 x 134.0g Na2C2O4 = 134 g Na2C2O4
1 mol Na2C2O4
67. How many particles are in 3.45 grams of silver acetate?
3.45g AgC2H3O2 x 1 mol AgC2H3O2 x 6.02E23 part AgC2H3O2 = 1.24x1022 part AgC2H3O2
166.9 g AgC2H3O2
1 mol AgC2H3O2
68. How many molecules are in 1.26 x 1018 amu of LiCl?
1.26E18 amu LiCl x 1.66E-24g LiCl x 1 mol LiCl x 6.02E23 molec LiCl =2.97x1016molec LiCl
1 amu LiCl
42.4g LiCl
1 mol LiCl
69. Calculate the percent composition for each element in ammonium
phosphate. NH4+ PO4 -3  (NH4)3PO4
14.0(3) + 1.0 (12) + 31.0 + 16.0(4) = 149.0 g/mol
%N = 14.0(3) / 149.0 * 100 = 28.2 %N
%H = 1.0(12) / 149.0 * 100 = 8.1 %H
%P = 31.0 / 149.0 * 100 = 20.8 %P
%O = 16.0(4) / 149.0 * 100 = 43.0 %O
70. Calculate the empirical formula for the compound that is 49.48 % carbon,
28.87 % nitrogen, 16.49 % oxygen, and 5.15 % hydrogen.
49.38gC x 1 mol C = 4.12 mol C / 1.03 mol = 4
12.0 g C
28.87gN x 1 mol N = 2.06 mol N / 1.03 mol = 2
14.0 g N
16.49gOx 1 mol O = 1.03 mol O / 1.03 mol = 1
16.0 g O
5.15gH x 1mol H = 5.15 mol H / 1.03 mol = 5
1.0 g H
C4N2OH5
71. Calculate the molecular formula for the compound that is 71.65 %
chlorine, 24.27 % carbon, and 4.07 % hydrogen. The molar mass is
247.5 g/mol.
71.65gCl x 1 mol Cl = 2.02 mol Cl / 2.02 mol = 1
35.5 g Cl
24.27gC x 1 mol C = 2.02 mol C / 2.02 mol = 1
12.0 g C
4.07gHx 1 mol H = 4.07 mol H / 2.02 mol = 2
1.0 g H
ClCH2
247.5 g/mol = 5
49.5 g/mol
Cl5C5H10
Chemical Reactions
Reactants and Products
Symbols in Equations
Balancing Equations – Use of Coefficients
72. Balance
a.
b.
c.
the following equations.
___ C2H5OH + _3_ O2  _2_ CO2 + _3_ H2O
___ CaC2 + _2_ H2O  ___ Ca(OH)2 + ___ C2H2
___ Cl2 + _2_ KI  _2_ KCl + ___ I2
d. _4_ NH3 + _3_ Cl2  _3_ NH4Cl + ___ NCl3
e. ___ PbCl2 + ___ K2SO4  ___ PbSO4 + _2_ KCl
73. Write and balance the following equations include state symbols.
a. Solid iron (III) oxide is heated strongly in carbon monoxide gas, it
produces elemental iron and carbon dioxide gas.
Fe2O3 (s) + 3 CO (g)  2 Fe (s) + 3 CO2 (g)
b. Acetylene gas (C2H2) is burned in air to produce carbon dioxide
gas and water vapor.
2 C2H2 (g) + 5 O2 (g)  4 CO2 (g) + 2 H2O (g)
74. Write word equations for the following reactions.
a. 2Ag (s) + H2S (g)  Ag2S (s) + H2 (g)
Solid silver reacts with hydrosulfuric acid to produce solid silver sulfide
and hydrogen gas.
b. 2FeO (s) + C (s)  2Fe (l) + CO2 (g)
Solid iron (II) oxide reacts with solid carbon to produce molten (liquid)
iron and carbon dioxide gas.
Reactions in Aqueous Solutions
Solubility Rules
Activity Series
Writing Molecular, Complete Ionic, and Net Ionic Equations
Single Displacement Reactions
Double Displacement Reactions
Combustion Reactions – Complete and Incomplete
Decomposition Reactions
Synthesis Reactions
75. Determine whether the following compounds are soluble or insoluble.
a. sodium acetate soluble
b. silver hydroxide insoluble
c. lithium sulfide soluble
d. colbalt (II) sulfate soluble
76. Predict the products and balance the following equations. Include physical
state symbols.
a. 2 C4H10 (g) + 13 O2 (g)  8 CO2 (g) + 10 H2O (g)
combustion
b. SO2 (g) + H2O (l)  H2SO3 (aq)
synthesis
c. Ca (s) + H2O (l)  CaO (s) + H2 (g)
single displacement, redox
d. MgSO3 (aq)  MgO (s) + SO2 (g)
decomposition
e. AgC2H3O2 (aq) + KBr (aq)  AgBr (s) + KC2H3O2 (aq)
Double displacement, precipitation
77. Classify 76a-e classify the reactions in as many ways as possible.