CHM13P

Multiple ChoiceIdentify the choice that best completes the statement or answers the question.

____ 1. What is the molecular formula for hydrogen chloride?a. HClO2 c. HClO3

b. HCl d. HClO4

____ 2. A compound contains sulfur, oxygen, and chlorine. Analysis shows that it contains by mass 26.95% sulfur and 59.61% chlorine. What is the simplest formula for this compound?a. S2OCl2 c. SOCl2

b. SOCl d. SO2Cl2

____ 3. A 4.628-g sample of an oxide of iron was found to contain 3.348 g of iron and 1.280 g of oxygen. What is simplest formula for this compound?a. FeO c. Fe2O3

b. Fe3O4 d. Fe3O2

____ 4. What mass of FeCl3 would contain the same total number of ions as 16.8 g of Al2(SO4)3?a. 10.8 g c. 7.96 gb. 9.95 g d. 8.01 g

____ 5. A sample of lead ore has a density of 8.80 g/mL. It is composed of two lead compounds: lead oxide, PbO (density 9.10 g/mL) and lead selenide, PbS (density 8.10 g/mL). What is the percent of the ore is lead oxide?a. 89.0 % c. 96.7 %b. 92.0 % d. 70.0 %

____ 6. The empirical formula of a compound is CHBr and its molecular weight is 185. What is its molecular formula? (atomic weights: C 12.01, H 1.008, Br 79.90)a. CH2Br c. C3H3Br3

b. C2H2Br2 d. C2HBr____ 7. Balancing a chemical equation so that it obeys the law of conservation of matter requires:

a. Changing the formulas of the products and reactants.b. Adjusting the coefficients in front of the formulas so there are the same number and type

of atom on both sides of the equation.c. Keeping the total charge the same on both sides of the equation.d. Making sure the reactants and products are in the same phase.

____ 8. How many molecules of O2 would react with 56 C2H6 molecules according to the following balanced equation?     2C2H6 7O2 4CO2 6H2Oa. 112 c. 196b. 784 d. 50

____ 9. What volume of 0.130 M HCl solution will just react with 0.424 gram of Ba(OH)2?     2HCl Ba(OH)2 BaCl2 2H2Oa. 38.1 mL c. 32.6 mLb. 24.1 mL d. 18.6 mL

____ 10. Which one of the following is an alkaline earth metal?a. bismuth, Bi c. magnesium, Mgb. tin, Sn d. potassium, K

____ 11. Which one of the following is a strong electrolyte?a. HNO3 c. HNO2

b. CH3COOH d. NH3

____ 12. Determine the oxidation number of the underlined element in LiAlH4.a. 2 c. 1b. 0 d. 1

____ 13. Determine the oxidation number of the underlined element in H2P2O7.a. 6 c. 4b. 5 d. 3

____ 14. When two nonmetals combine, ____.a. they form a binary ionic compound.b. they neutralize the acid formed in the reaction.c. they form a binary covalent compound.d. they release hydrogen gas.

____ 15. Which of the following reactions is a decomposition reaction?a. C3H8(g) 5O2(g) 3CO2(g) 4H2O( ) c. 2KClO3(s) 2KCl(s) 3O2(g)b. Fe2O3(s) 3CO(g) 2Fe(s) 3CO2(g) d. 2H2(g) O2(g) 2H2O( )

____ 16. What ions are almost completely removed from solution when 0.1 M aqueous solutions of HBr and Pb(CH3COO)2 are mixed? Choose the response that includes all the ions removed.

I. H+

II. Br-

III. Pb2+

IV. CH3COO-

a. II, III and IV c. III and IVb. I, II, III and IV d. II and III

____ 17. The mass number of an atom is the number of ____ in the atom.a. neutrons c. electrons plus the number of neutronsb. protons plus the number of neutrons d. protons plus the number of electrons

____ 18. Give the number of protons, neutrons, and electrons in an atom of the 90Sr isotope.a. 90 p, 38 n, 90 e c. 38 p, 52 n, 38 eb. 52 p, 38 n, 52 e d. 38 p, 90 n, 38 e

____ 19. A hypothetical element consists of four isotopes having the following percentage natural abundance and isotopic masses. What is its atomic weight? isotope 1: 16.06% (52.100 amu); isotope 2: 28.36% (53.097 amu); isotope 3: 42.60% (54.093 amu); isotope 4: 12.98% (55.090 amu).a. 53.262 amu c. 53.487 amub. 53.314 amu d. 53.620 amu

____ 20. The five isotopes of nickel occur in the following percentages with the following isotopic masses. The atomic weight is 58.69 amu. What is the isotopic mass of 60Ni? (Choose the closest answer.)

Isotope Mass (amu) %58Ni 57.935 68.2760Ni ? 26.1061Ni 60.931   1.1362Ni 61.928   3.5964Ni 63.928   0.91

a. 59.93 amu c. 60.57 amub. 59.31 amu d. 58.62 amu

____ 21. Which response lists all the true statements about the four quantum numbers?

I. n principal quantum number, n 1,2,3, . . .II. l angular momentum quantum number, l 0,1,2,3, . . ., (n 1)III. ml magnetic quantum number, ml 0, 1, . . ., lIV. ms spin quantum number,

ms

a. I and III c. I, II, and IVb. II, III, and IV d. II and III

____ 22. Which statement is false?a. The fifth shell (or major energy level) has one set of f orbitals.b. A set of p orbitals can accommodate a maximum of 6 electrons.c. There are 10 d orbitals in a set.d. None of the p orbitals are spherically symmetric.

____ 23. Identify the following orbital.

a. dxy c. fz

b. d.

____ 24. An element with the outermost electron configuration ns2np3 would be in Groupa. IIIA c. VIIAb. VA d. IIA

____ 25. How many neutrons does an atom of chlorine-35 ( ) have?a. 52 c. 17b. 35 d. 18

____ 26. How many atomic orbitals are there in the 4d subshell?a. 2 c. 4b. 3 d. 5

____ 27. Choose the response that includes all of the listed elements that are d-transition elements, and no others.

I. TiII. MoIII. TlIV. KrV. U

a. IV and V c. III and IVb. I and II d. II and III

____ 28. Which of the following statements is false?a. Transition elements have larger atomic radii than the preceding IA and IIA elements in the

same period because transition elements have electrons in their d orbitals.b. Electrons in inner shells screen, or shield, electrons in outer shells from the full effect of

the nuclear charge.c. The atomic radii of representative elements decrease from left to right across a period

(horizontal row in the periodic table).d. Within a family (vertical group in the periodic table) of representative elements atomic

radii increase from top to bottom.____ 29. Which ion or atom has the largest radius?

a. Sr c. Rbb. Se d. Br

____ 30. Oxygen was discovered by Priestley in 1774 when he observed the ____.a. thermal decomposition of mercury(II) oxide, HgOb. electrolysis of waterc. results of fractional distillation of aird. the thermal decomposition of potassium chlorate, KClO

____ 31. What do elements in the same vertical column of the periodic table have in common?a. the same physical propertiesb. similar chemical propertiesc. the same electron configurationd. the same number of filled electron energy levels

____ 32. Which Lewis Dot Formula is incorrect?a. c.

b. d.

____ 33. Which Lewis dot notation for atoms and ions is correct for the reaction for the formation of calcium phosphide?a.

b.

c.

d.

____ 34. Which of the following statements is the best definition of valence electrons?a. The electrons that are paired.b. The electrons that are unpaired.c. The electrons in the p orbitalsd. The electrons occupying the highest energy (outermost) level.

____ 35. What is the formula for the binary ionic compound of lithium and nitrogen?a. LiN c. Li Nb. LiN d. Li N

____ 36. A chemical bond formed by two atoms sharing one or more pairs of electrons is called a (or an) ____ bond.a. coordinate covalent c. nonpolarb. ionic d. covalent

____ 37. The internuclear distance at which the attractive and repulsive forces balance in a covalent bond is called the ____.a. bond length d. single bondb. bond energy e. none of thesec. stabilization length

____ 38. The total number of valence electrons that must be shown in the dot formula for the C H Cl FO molecule is ____. (It is not necessary to draw the dot formula.)a. 50 c. 48b. 42 d. 46

____ 39. When writing the relationship among N, A, and S for H CO , N = ____, A = ____, and S = ____.

N A S N A S

a. 40 16 14 c. 36 24 12b. 34 22 12 d. 34 24 10

____ 40. Draw the dot formula for acetylene, C H . The two carbon atoms are bonded together and each carbon is bonded to one hydrogen. Each carbon-hydrogen bond is a ____ bond and each carbon-carbon bond is a ____ bond.a. single, triple c. double, doubleb. single, double d. double, single

____ 41. How many lone pairs of electrons are there on the Xe atom in the XeF molecule?a. four c. threeb. zero d. two

____ 42. How many resonance structures does the nitrate ion, NO -, have?a. 3 c. 0b. 2 d. 1

____ 43. How many resonance structures does the bicarbonate ion, HCO -, have?a. 2 c. 1b. 3 d. 4

____ 44. How many resonance structures does O have?a. 4 c. 0b. 1 d. 2

____ 45. Which molecule has the most polar covalent bond?a. HCl c. N2

b. IBr d. PH3

____ 46. Which of the following statements concerning polar molecules is false?a. There must be an odd number of polar bonds so that their polarities not cancel.b. A molecule with symmetrically arranged polar bonds can be polar if the central atom is

bonded to atoms of different elements.c. If there are more than one polar bond, they must not be symmetrically arranged so that

their polarities cancel.d. There must be at least one polar bond or one unshared pair of electrons on the central

atom.____ 47. The hybridization associated with the central atom of a molecule in which all the bond angles are 109.5° is

____.a. sp3d c. sp3d2

b. sp d. sp3

____ 48. The bond angles associated with sp3d2 hybridization are ____.a. 109° c. 90° and 180°b. 90° and 120° d. 120°

____ 49. Which of the following statements about polar molecules is false?a. A molecule with 180o bond angles can be polar.b. A molecule with 120o bond angles can be polar.c. A molecule with polar bonds can be nonpolar.d. A molecule with only nonpolar bonds can be polar.

____ 50. Molecules such as NF3 are best described by assuming what kind of hybridization at the central atom?a. sp3d c. spb. sp3d2 d. sp3

____ 51. Which of the following species has square planar molecular geometry?

a. SF4 c. SO42-

b. XeF4 d. CH4

____ 52. Which of the following statements about multiple bonds is true?a. A sigma bond results from the side-on overlap of p atomic orbitals.b. sp3 hybridization in carbon is associated with one double bond and two single bonds.c. A double bond consists of two sigma bonds.d. sp2 hybridization in carbon is associated with one double bond and two single bonds.

____ 53. How many sigma ( ) bonds and how many pi ( ) bonds does the acetylene molecule contain?a. 3 and 1 c. 5 and 1 b. 3 and 2 d. 2 and 2

____ 54. Which response includes all of the molecules listed that have the same molecular geometry as electronic geometry, and only those molecules?

    BCl3, AsF5, NF3, H2Sa. c.

b. d.

____ 55. Which, if any, of the compounds listed are not sp3d hybridized at the central atom?

I. BF3

II. AsI5

III. SF4

IV. BrF5

V. XeF4

a. III and IV c. all are sp3d hybridizedb. III and V d. I, IV, and V

____ 56. What is the molecular geometry of the species, ICl2+.

a. linear c. tetrahedralb. angular d. trigonal planar

____ 57. Which of the following can be a Brønsted-Lowry acid?a. H2O c. CH4

b. H2 d. NaOH____ 58. What is the formula and molarity of the salt produced by the reaction of 17 mL of 0.33 M H2SO4 and 44 mL

of 0.23 M Sr(OH)2?a. SrH2, 0.0920 M c. SrSO4, 0.0920 Mb. SrSO4, 9.2 10-5 M d. Sr(OH)2, 0.165 M

____ 59. A sample of impure iron reacts with exactly 28.3 mL of 0.100 M HCl. How many grams of iron were contained in the sample?     FeS (s) + 2HCl (aq) H2S (g) + FeCl2 (aq)a. 0.158 g c. 0.316 gb. 79.0 g d. 0.079 g

____ 60. Balance this equation for a reaction in basic solution. What is the coefficient of H2O?     KOH + Cl2 KClO3 + KCl + H2Oa. 3 c. 2b. 6 d. 4

____ 61. In acidic solution MnO4- oxidizes H3AsO3, a weak acid, to H3AsO4, a weak acid, and is reduced to Mn2+.

Write the balanced net ionic equation for this reaction. How many H+ are there in the balanced equation?a. 4 c. 2b. 6 d. 1

____ 62. Write the balanced net ionic equation for the reaction of hydrogen sulfide with bromate ions, BrO3-, in acidic

solution to form sulfur and bromide ions. How many H+ are there in the balanced equation?a. zero c. 3b. 2 d. 6

____ 63. What volume of 0.0100 M KMnO4 solution is required to oxidize 42.5 mL of 0.0100 M FeSO4 sulfuric acid solution?     MnO4

- + 8H+ + 5Fe2+ Mn2+ + 5Fe3+ + 4H2Oa. 8.5 mL c. 16.0 mLb. 31.9 mL d. 80.0 mL

____ 64. What volume of 0.1066 M Na2S2O3 solution would be required to react with 24.32 mL of 0.1008 M I2 solution?     Na2S2O3 + I2 Na2S4O6 + NaI (unbalanced)a. 5.75 mL c. 11.50 mL

b. 34.50 mL d. 45.99 mL

____ 65. When household ammonia is mixed with bleach, NaOCl, toxic chlorine gas and hydrazine, N2H4 is produced. What volume of 0.75 M NH3 would react with 100 mL of 0.35 M NaOCl? NH3 + OCl- Cl2 + N2H4 (unbalanced)a. 23.5 Ml c. 100 mLb. 26 mL d. 47 mL

____ 66. A 50.0-mL sample of K2Cr2O7 solution oxidizes 1.500 g of Na2SO3 to Na2SO4. Cr2(SO4)3 is also produced. What is the molarity of the K2Cr2O7 solution?a. 2.96 M c. 0.0158 Mb. 0.0952 M d. 0.0794 M

____ 67. If 30.0 mL of 0.250 M HCl solution and 30.0 mL of 0.250 M NaOH are mixed, what is the molarity of the salt in the resulting solution? Assume that the volumes are additive.a. 0.0075 M c. 0.125 Mb. 0.0625 M d. 0.250 M

____ 68. What volume of 0.230 M potassium hydroxide solution, KOH, would completely neutralize 27.4 mL of 0.205 M sulfurous acid solution, H2SO3?a. 61.5 mL c. 24.4 mLb. 12.2 mL d. 48.8 mL

____ 69. A sample of helium occupies 1.40 L at standard conditions. What pressure will it exert in a 0.500 L vessel at 100.°C?a. 1.56 103 torr c. 371 torrb. 624 torr d. 2.91 103 torr

____ 70. A sample of nitrous oxide, N2O, occupies 1.65 L at STP. What is the mass of the sample?a. 18.9 g c. 22.1 gb. 28.6 g d. 32.4 g

____ 71. A 7.97 g sample of gas occupies 5.25 L at STP. What is the formula of the gas?a. CO2 c. PCl3

b. NO d. N2H4

____ 72. What mass of methane, CH4, is contained in a 500.-mL sample of CH4 at STP?a. 0.407 g c. 0.357 gb. 0.212 g d. 0.390 g

____ 73. Calculate the density of O2, in g/L, at STP.a. 0.714 g/L c. 1.62 g/Lb. 1.43 g/L d. 1.14 g/L

____ 74. A 5.00 L container contains CH4, H2, and Xe at 35°C with a total pressure of 1.81 atm. If there are equal moles of each gas, what is the partial pressure of H2?a. 0.603 atm c. 0.034 atmb. 1.81 atm d. 3.05 atm

____ 75. A mixture of gases containing 21.0 g of N2, 106.5 g of Cl2 and 12.0 g of He at 14°C is in a 50.0-L container. What is the total pressure in the vessel?a. 2.7 atm c. 2.5 atmb. 1.8 atm d. 2.2 atm

____ 76. Which of the following situations would one expect the most real gas behavior?a. He at 10°C c. NH3 at 5 atmb. CO2 at 100 atm d. CO at 25°C

____ 77. The van der Waals constant, b, in the relationship (P + )(V - nb) = nRT is a factor that corrects fora. the attractive forces between gas molecules.b. the volume occupied by the gas molecules.c. deviations in the gas constant, R.d. the average velocities of the gas molecules.

____ 78. Calculate the pressure (in atm) exerted by 1.00 mole of acetylene at 125°C in a 20.0-liter container. The van der Waals constants for acetylene are: a = 20.0 L2 • atm/mol2, b = 0.100 L/mol.a. 1.59 c. 1.64b. 0.485 d. 0.533

____ 79. Which liquid would evaporate most quickly at room temperature?a. Ethylene glycol, HO-CH2-CH2-OH, 62 g/molb. H2O, 18 g/molc. Vegetable oil, 895 g/mold. Gasoline, C8H18, 114 g/mol

____ 80. Calculate the amount of heat (in joules) required to convert 92.5 g of water at 25.0°C to steam at 108.0°C. (Sp. heat of H2O( ) = 4.18 J/g•°C, Sp. heat of H2O(g) = 2.03 J/g•°C, heat of vap. of H2O( ) = 2.260 kJ/g)

a. 6.43 105 J c. 3.05 104 Jb. 2.26 105 J d. 2.40 105 J

____ 81. Which one of the following statements is not applicable to ionic solids?a. Ionic solids have fairly high melting points.b. Most ionic solids are hard and brittle.c. Ionic solids are usually excellent conductors of electric current.d. The units that occupy the lattice points are ions.

____ 82. Which statement is false?a. About 26% of the total volume of any cubic close packed crystal lattice is empty space.b. Two solids that crystallize in the same kind of crystal lattice are said to be isomorphous.c. The size of an ion in a crystal is influenced by its environment, that is, by the other ions

surrounding it.d. An example of an amorphous solid is diamond.

____ 83. Which one of the following substances is incorrectly matched with the kind of solid it forms?

Substance Kind of Solid

a. sulfur dioxide molecular c. methane molecularb. lithium ionic d. calcium bromide ionic

____ 84. If the mole fraction of methyl alcohol in a solution (with only water) is 0.28, what is the mole fraction of the water?a. 0.62 c. 0.72b. 0.28 d. 1.28

____ 85. Calculate the boiling point of a solution prepared by dissolving 70.0 g of naphthalene, C10H8 (a nonvolatile nonelectrolyte), in 220.0 g of benzene, C6H6. The Kb for benzene = 2.53°C/m. The boiling point of pure benzene is 80.1°C.a. 73.8°C c. 106.3°Cb. 87.8°C d. 86.4°C

____ 86. Calculate the freezing point of a solution that contains 8.0 g of sucrose (C12H22O11) in 100. g of H2O. Kf for H2O = 1.86°C/m.a. - 0.044°C c. 0.04°Cb. - 0.44°C d. - 0.22°C

____ 87. Calculate the freezing point of a solution that contains 68.4 g of sucrose (table sugar) in 300. g of water. One mole of sucrose is 342 g. Kf for H2O = 1.86°C/m.a. -0.372°C c. -1.24°Cb. -0.186°C d. -0.558°C

____ 88. When 35.0 g of an unknown nonelectrolyte is dissolved in 220.0 g of benzene, the solution boils at 83.2°C. Calculate the molecular weight of the unknown nonelectrolyte. The Kb for benzene = 2.53°C/m. The boiling point of pure benzene is 80.1°C.a. 156 g/mol c. 20.3 g/molb. 183 g/mol d. 130 g/mol

____ 89. How much heat is released or absorbed in the reaction of 10.0 grams of SiO2 (quartz) with excess hydrofluoric acid?

SiO2(s) + 4HF(aq) SiF4(g) + 2H2O( )

H-910.9 -320.8 -1615 -285.8

a. 1.25 kJ released c. 6.56 kJ releasedb. 11.3 kJ released d. 1.25 kJ absorbed

____ 90. Which statement is false?a. H is equal to E for the process: 2H2(g) + O2(g) 2H2O(g).b. No work is done in a reaction occurring in a bomb calorimeter.c. H is often nearly equal to E.d. The thermodynamic quantity most easily measured in a "coffee cup" calorimeter is H.

____ 91. The reaction of 1.00 mole of H2(g) with 0.500 mole of O2(g) to produce 1.00 mole of steam, H2O(g), at 100°C and 1.00 atm pressure evolves 242 kJ of heat. Calculate E per mole of H2O(g) produced. The universal gas constant is 8.314 J/mol•K.a. +240 kJ c. +242 kJb. -242 kJ d. -240 kJ

____ 92. Calculate S0 for the reaction below at 25°C. S0 for SiH4 = 204.5 J/mol•K, for O2(g) = 205.0 J/mol•K, for SiO2(s) = 41.84 J/mol•K, for H2O( ) = 69.91 J/mol•K.     SiH4(g) + 2O2(g) SiO2(s) + 2H2O( )a. -677.0 J/K c. -353.5 J/Kb. -880.3 J/K d. -432.8 J/K

____ 93. At 100 K the reaction below obeys the rate law rate = k[AB2]2 where k = 5.7 M-1•s-1.     2AB2 A2 + 2B2

What would the concentration of AB2 be after 60 minutes if the initial concentration was 1.45 mol/L?a. 2.0 10-5 M c. 4.9 10-5 Mb. 1.9 10-4 M d. 2.4 10-5 M

____ 94. What would be the activation energy of a reaction if its rate constant at 35°C was double the value of its rate constant at 25°C?a. 8.12 kJ/mol c. 52.9 kJ/molb. 68.3 J/mol d. 63.8 kJ/mol

____ 95. A catalysta. increases H for the process.b. increases the rate at which equilibrium is reached without changing the equilibrium

constant.c. increases the amount of products present at equilibrium.d. lowers S for the process.

____ 96. Consider the gas phase system below at a high temperature. The form of the expression for the equilibrium constant, Kc, ____.     4NH3 + 5O2 4NO + 6H2Oa.

is Kc =

c.

is Kc = b.

is Kc =

d. cannot be determined without rate data

____ 97. What is the equilibrium constant expression for the following reaction?     C3H8(g) + 5 O2(g) 3 CO2(g) + 4 H2O( )a. c.

b. d.

____ 98. What is the value of Kc for the reaction 2A(g) + 3B(g) 2C(g) + D(g) if at equilibrium [A] = 0.60 M, [B] = 0.30 M, [C] = 0.10 M and [D] = 0.50 M?a. 2.4 c. 0.088b. 0.15 d. 0.51

____ 99. The Kc for the following reaction is 56.2 at 305°C.     A2(g) + B2(g) 2 C(g)

If a reaction is initiated with 2.4 M of each substance, what is the equilibrium concentration of C?a. 4.3 M c. 5.7 Mb. 1.2 M d. 2.4 M

____ 100. Consider the reversible reaction at equilibrium at 392°C.     2A(g) + B(g) C(g)

The partial pressures are found to be: A: 6.70 atm, B: 10.1 atm, C: 3.60 atm. What is the concentration of B at equilibrium?a. 0.200 M c. 1.64 Mb. 0.185 M d. 1.13 M