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MC_Chem1A_Sp08_LecExamFinal
Multiple Choice
Identify the choice that best completes the statement or answers the question.
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1. You can identify a metal by carefully determining its density. A 8.44 g piece of an unknown metal is 1.25 cm
long, 2.50 cm wide, and 1.00 cm thick. What is a possible identity of the element?
a. nickel, 8.90 g/cm3
b. aluminum, 2.70 g/cm3
c. titanium, 4.54 g/cm3
d. zirconium, 6.51 g/cm3
e. chromium, 7.20 g/cm3
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2. What is the correct answer to the following expression: (72.61 - 68.59)  18.76? Carry out the subtraction
operation first.
a. 7  101
b. 75
c. 75.4
d. 74.542
e. 75.5415
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3. Express 0.38300 in exponential notation.
a. 3.8300  10-1
b. 3.83  10-1
c. 3.830  10-2
d. 3.83  101
e. 3.8300  101
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4. The reaction of 10.0 g H2(g) with 10.0 g O2(g) yields 8.43 g H2O(g). What is the percent yield of this
reaction?
a. 9.43%
b. 27.3%
c. 42.2%
d. 66.8%
e. 74.9%
____
5. Bromine has two naturally occurring isotopes. The average mass of bromine is 79.904 u. If 50.54% of
bromine is found as bromine-79 (78.9183 u), what is the mass of the other isotope?
a. 79.82 u
b. 79.97 u
c. 80.91 u
d. 81.93 u
e. 82.91 u
____
6. All of the following statements are true EXCEPT
a. for any neutral element, the number of protons and electrons are equal.
b. electrons and protons have equal mass, but opposite charges.
c. the mass number is the sum of the number of protons and neutrons.
d. the atomic number equals the number of protons.
e. isotopes of an element have identical atomic numbers.
____
7. The density of lithium is 0.546 g/cm3. What volume is occupied by 1.96  1023 atoms of lithium?
a. 0.0859 cm3
b. 0.596 cm3
c. 4.14 cm3
d. 5.63 cm3
e. 39.0 cm3
____
8. Which of the following formulas is not correct?
a. Al2(SO4)3
b. NaClO3
c. Ba2O3
d. Mg(NO3)2
e. KH2PO4
____
9. Which of the following compounds will be soluble in water: KNO3, Ca3(PO4)2, CuCl2, and Fe2S3?
a. KNO3 and Ca3(PO4)2
b. KNO3 and CuCl2
c. Ca3(PO4)2 and Fe2S3
d. CuCl2 and Fe2S3
e. KNO3, Ca3(PO4)2, and Fe2S3
____ 10. Which of the following species are strong acids: HNO3, HBr, H3PO4,CH3CO2H, and HSO4-?
a. HNO3 and HBr
b. HNO3 and H3PO4
c. HBr and HSO4d. H3PO4, CH3CO2H, and HSO4e. HNO3, H3PO4, and HSO4____ 11. What is the oxidation number of each atom in potassium nitrate, KNO3?
a. K = +1, N = -3, O = -2
b. K = +1, N = +5, O = -2
c. K = +1, N = -3, O = +2
d. K = -1, N = +3, O = -2
e. K = 0, N = 0, O = 0
____ 12. The pH of an aqueous KOH solution is 12.38. What is the hydrogen ion concentration of this solution?
a. 8.1  10-14 M
b. 4.2  10-13 M
c. 8.1  10-6 M
d. 0.21 M
e. 1.1 M
____ 13. If 5.00 mL of 0.314 M KOH is diluted to exactly 125 mL with water, what is the concentration of the
resulting solution?
a. 5.02  10-4 M
b. 1.26  10-2 M
c. 0.127 M
d. 0.281 M
e. 7.85 M
____ 14. Hydrazine, N2H4, is a liquid used as a rocket fuel. It reacts with oxygen to yield nitrogen gas and water.
N2H4() + O2(g)  N2(g) + 2 H2O()
The reaction of 3.80 g N2H4 evolves 73.7 kJ of heat. Calculate the enthalpy change per mole of hydrazine
combusted.
a. -8.74 kJ/mol
b. -19.4 kJ/mol
c. -2.80  102 kJ/mol
d. -622 kJ/mol
e. -8.98  103 kJ/mol
____ 15. If the energy of 1.00 mole of photons is 441 kJ, what is the wavelength of the light?
a. 271 nm
b. 451 nm
c. 680 nm
d. 732 nm
e. 891 nm
____ 16. What type of orbital is designated n = 4,  = 3, m = -3?
a. 4s
b. 4p
c. 4d
d. 4f
e. none
____ 17. Which of the following orbitals might have m = -2?
a. s
b. s and p
c. p and d
d. d and f
e. p, d, and f
____ 18. How many electrons can be described by the quantum numbers n = 7,  = 1?
a. 0
b. 2
c. 6
d. 7
e. 14
____ 19. What is a possible set of quantum numbers for the unpaired electron in the orbital box diagram below?
a.
b.
c.
d.
e.
n = 3,  = 1, m = -1, ms = +1/2
n = 3,  = 2, m = -1, ms = -1/2
n = 3,  = 2, m = -2, ms = +1/2
n = 4,  = 0, m = 0, ms = +1/2
n = 4,  = 1, m = -1, ms = +1/2
____ 20. Which one of the following statements is INCORRECT?
a. Ionization energy is always a positive value.
b.
c.
d.
e.
Ionization energy is the energy required to remove an electron from a gaseous atom.
For any element, the second ionization energy is larger than the first ionization energy.
Ionization energy decreases across a periodic of the periodic table.
Ionization energy decreases down a group of the periodic table
____ 21. Which of the following are resonance structures for the formate ion, HCO2-?
a.
b.
c.
d.
e.
1 and 2
2 and 3
3 and 4
1, 3, and 4
2, 3, and 4
____ 22. To prepare 1.000 kg of 5.5% by mass KCl(aq), one may dissolve
a. 994.5 g KCl in 5.5 g of water.
b. 5.5 g KCl in 994.5 g of water.
c. 5.5 g KCl in 1000.0 g of water.
d. 55 g KCl in 945 g of water.
e. 55.0 g KCl in 1000.0 g of water.
____ 23. What is the mole fraction of 1.98 m Fe(NO3)3(aq)? The molar mass of Fe(NO3)3 is 241.9 g/mol and the molar
mass of water is 18.02 g/mol.
a. 0.0345
b. 0.0641
c. 0.324
d. 0.479
e. 0.863
____ 24. The vapor pressure of pure water at 45 C is 71.9 mm Hg. What is the vapor pressure of a mixture of 21.0 g
sucrose (C12H22O11, molar mass 342.3 g/mol) and 79.0 g water?
a. 0.992 mm Hg
b. 15.1 mm Hg
c. 19.1 mm Hg
d. 55.8 mm Hg
e. 70.9 mm Hg
____ 25. Which of the following aqueous solutions should have the lowest freezing point?
a. pure H2O
b. 1 m NaBr
c. 1 m Ca(NO3)2
d. 1 m NH3
e. 1 m C6H12O6
____ 26. The freezing point depression constant for water is -1.86 C/m. At what temperature will a solution containing
7.99 g BaCl2 and 52.0 g H2O begin to freeze? Assume that no ion-pairing occurs between Ba2+ and Cl-.
a.
b.
c.
d.
e.
-4.12 C
-2.75 C
-1.37 C
-0.857 C
-0.248 C
____ 27. The osmotic pressure of blood is 7.65 atm at 37 C. What mass of glucose (C6H12O6, molar mass = 180.2
g/mol) is needed to prepare 5.00 L of solution for intravenous injection? The osmotic pressure of the glucose
solution must equal the osmotic pressure of blood. (R = 0.08206 L·atm/mol·K)
a. 1.50 g
b. 54.2 g
c. 126 g
d. 271 g
e. 2270 g
____ 28. What mass of He contains the same number of atoms as 5.0 g Kr?
a. 0.24 g
b. 0.80 g
c. 1.2 g
d. 5.0 g
e. 1.0  102 g
____ 29. All of the following are named correctly EXCEPT
a. LiClO4; lithium perchlorate.
b. CaHPO4; calcium hydrogen phosphide.
c. NaCN; sodium cyanide.
d. Mg(OH)2; magnesium hydroxide.
e. CaSO3; calcium sulfite.
____ 30. What is the mass percent of each element in dichloromethane, CH2Cl2?
a. 10.06% C, 60.24% H, 29.70% Cl
b. 20.00% C, 20.00% H, 60.00% Cl
c. 24.10% C, 3.11% H, 72.79% Cl
d. 33.87% C, 0.22% H, 65.91% Cl
e. 14.14% C, 2.37% H, 83.48% Cl
____ 31. The compound P4S3 is used in matches. It reacts with oxygen to produce P4O10 and SO2. The unbalanced
chemical equation is shown below.
P4S3(s) + O2(g)  P4O10(s) + SO2(g)
What mass of O2 will react with 0.641 grams of P4S3?
a. 0.0466 g
b. 0.0932 g
c. 0.186 g
d. 0.372 g
e. 0.746 g
____ 32. What is the net ionic equation for the reaction of aqueous lead(II) nitrate with aqueous sodium bromide?
a. Pb(NO3)2(aq) + 2 NaBr(aq)  PbBr2(aq) + 2 NaNO3(s)
b. Na+(aq) + NO3-(aq)  NaNO3(s)
c. Pb2+(aq) + 2 Br-(aq)  PbBr2(s)
d. Pb2+(aq) + 2 Na+(aq)  PbNa2(s)
e. Pb(NO3)2(aq) + 2 NaBr(aq)  PbBr2(s) + 2 NaNO3(aq)
____ 33. If 50.0 g H2O at 13.6 C is combined with 85.0 g H2O at 93.7 C, what is the final temperature of the
mixture? The specific heat capacity of water is 4.184 J/g·K.
a. 26.1 C
b. 40.0 C
c. 56.1 C
d. 64.0 C
e. 80.1 C
____ 34. Which of the following sets of quantum numbers refers to a 4p orbital?
a. n = 1,  = 1, m = -1
b. n = 1,  = 2, m = -1
c. n = 4,  = 1, m = 0
d. n = 4,  = 2, m = -1
e. n = 4,  = 3, m = +2
____ 35. What 1+ ion has the following ground state electron configuration?
a.
b.
c.
d.
e.
K+
Rb+
In+
Tl+
Y+
____ 36. Use VSEPR theory to predict the molecular geometry of CS2.
a. linear
b. bent
c. trigonal-planar
d. tetrahedral
e. octahedral
____ 37. What volume of CO2 at 15 C and 1.50 atm contains the same number of molecules as 0.410 L of O2 at 35 C
and 3.00 atm?
a. 0.192 L
b. 0.219 L
c. 0.767 L
d. 0.820 L
e. 1.14 L
____ 38. If a gas effuses 1.618 times faster than Kr, what is its molar mass?
a. 18.02 g/mol
b. 28.01 g/mol
c. 32.01 g/mol
d. 51.79 g/mol
e. 65.88 g/mol
____ 39. Ammonia, NH3, is used as a refrigerant. At its boiling point of -33 C, the enthalpy of vaporization of
ammonia is 23.3 kJ/mol. How much heat is required to vaporize 355 g of ammonia at -33 C?
a. 1.12 kJ
b. 152 kJ
c. 251 kJ
d. 486 kJ
e. 8.27  103 kJ
____ 40. Which of the following phase transitions is endothermic?
a. gas to solid
b. liquid to gas
c. liquid to solid
d. gas to liquid
e. none of the above
MC_Chem1A_Sp08_LecExamFinal
Answer Section
MULTIPLE CHOICE
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B
PTS: 1
OBJ: 1.4 Physical Properties
C
PTS: 1
OBJ: 1.8 Mathematics of Chemistry
A
PTS: 1
OBJ: 1.8 Mathematics of Chemistry
E
PTS: 1
4.4 Reactions in which One Reactant is Present in Limited Supply
C
PTS: 1
OBJ: 2.4 Atomic Weight
B
PTS: 1
OBJ: 2.3 Isotopes
C
PTS: 1
OBJ: 2.5 Atoms and the Mole
C
PTS: 1
OBJ: 3.3 Ionic Compounds: Formulas | Names | and Properties
B
PTS: 1
OBJ: 5.1 Properties of Compounds in Aqueous Solution
A
PTS: 1
OBJ: 5.3 Acids and Bases
B
PTS: 1
OBJ: 5.7 Oxidation-Reduction Reactions
B
PTS: 1
OBJ: 5.9 pH | A Concentration Scale for Acids and Bases
B
PTS: 1
OBJ: 5.8 Measuring Concentrations of Compounds in Solution
D
PTS: 1
OBJ: 6.5 Enthalpy Changes for Chemical Reactions
A
PTS: 1
OBJ: 7.2 Planck | Einstein | Energy | and Photons
D
PTS: 1
OBJ: 7.5 Quantum Mechanical View of the Atom
D
PTS: 1
OBJ: 7.5 Quantum Mechanical View of the Atom
C
PTS: 1
OBJ: 8.2 The Pauli Exclusion Principle
E
PTS: 1
OBJ: 8.4 Atomic Electron Configurations
D
PTS: 1
OBJ: 8.6 Atomic Properties and Periodic Trends
C
PTS: 1
OBJ: 9.5 Resonance
D
PTS: 1
OBJ: 14.1 Units of Concentration
A
PTS: 1
OBJ: 14.1 Units of Concentration
E
PTS: 1
OBJ: 14.4 Colligative Properties
C
PTS: 1
OBJ: 14.4 Colligative Properties
A
PTS: 1
OBJ: 14.4 Colligative Properties
D
PTS: 1
OBJ: 14.4 Colligative Properties
A
PTS: 1
OBJ: 2.5 Atoms and the Mole
B
PTS: 1
OBJ: 3.3 Ionic Compounds: Formulas | Names | and Properties
E
PTS: 1
OBJ: 3.6 Describing Compound Formulas
E
PTS: 1
4.3 Mass Relationships in Chemical Reactions: Stoichiometry
C
PTS: 1
OBJ: 5.2 Precipitation Reactions
D
PTS: 1
OBJ: 6.2 Specific Heat Capacity and Heat Transfer
C
PTS: 1
OBJ: 7.5 Quantum Mechanical View of the Atom
C
PTS: 1
OBJ: 8.5 Electron Configurations of Ions
A
PTS: 1
OBJ: 9.7 Molecular Shapes
C
PTS: 1
OBJ: 12.2 Gas Laws: The Experimental Basis
C
PTS: 1
OBJ: 12.7 Effusion and Diffusion
D
PTS: 1
OBJ: 13.5 Properties of Liquids
40. ANS: B
PTS: 1
OBJ: 13.5 Properties of Liquids