Download 7 - Mona Shores Blogs

7. At constant temperature, the behavior of a sample of a real gas more closely approximates that of an
ideal gas as its volume is increased because the
a. collisions with the walls of the container become less frequent
b. average molecular speed decreases
c. molecules have expanded
d. average distance between molecules become greater
e. average molecular kinetic energy decreases
8. A sealed vessel contains 0.200 mole of oxygen gas, 0.100 mole of nitrogen gas, and 0.200 mole of argon
gas. The total pressure of the gas mixture is 5.00 atm. The partial pressure of the argon is
a. 0.200 atm
b. 0.500 atm
c. 1.00 atm
d. 2.00 atm
e. 5.00 atm
9. A sample of CaCO3 (molecular weight 100.) was reported as being 28.0 percent Ca. Assuming no
calcium was present in any impurities, the percent CaCO3 in the sample is
a. 28.0%
b. 42.0%
c. 56.0%
d. 70.0%
e. 100.0%
10. 2 Al(s) + 6HCl(aq)  2AlCl3(aq) + 3H2(g)
According to the reaction above, about how many grams of aluminum (atomic weight 27) is
necessary to produce 0.60 mole of hydrogen gas at 25C and 1.00 atm?
a.
1.2 g
b. 11 g
c. 16 g
d. 24 g
e. 32 g
11. A sample of a pure compound was found to contain 1.201 g of carbon, 0.202 g of hydrogen, and 7.090
g of chlorine. What is the empirical formula for the compound?
a. CHCl3
b. CH2Cl
c. CH2Cl2
d. CH3Cl
e. C2H2Cl4
12. A magnesium atom differs from a magnesium ion (Mg2+) in that the atom has
a. 3s electrons
c. a greater stability
b. a higher ionization energy
d. a smaller radius
e. fewer subshells
13. What formula would be expected for a binary compound of barium and nitrogen?
a. Ba3N2
b. Ba2N3
c. Ba2N
d. BaN2
e. BaN
14. What is the geometric shape of the ClF4+ ion?
a. see-saw b. octahedron c. square planar d. tetrahedral
15. What molecule as sp2 hybridization of a carbon atom?
a. CH2CH2
b. CH3CH3
c. CHCH
d. CH4
e. trigonal pyramidal
e. CO2
16. Which of the following changes always results in a negative E?
a. the system absorbs heat and does work
b. the system gives off heat and does work
c. the system absorbs heat and has work done on it
d. the system gives off heat and has work done on it.
17. The value of H for the following reaction is -126 kJ. Determine the amount of heat in kJ that would
be evolved by the reaction of 25.0 g of Na2O2 with water
2Na2O2 (s) + 2H2O (l)  4NaOH (s) + O2 (g)
a. 20.2
b. 40.4
c. 67.5
d. 80.8
18. When 29 J of heat is transferred to 15 g of lead at 22C, the temperature of the lead increases to
37C. What is the heat capacity (in J/gC) of lead?
a. 7.8
b. 1.9
c. 29
d. 0.13
19. Determine the shape and polarity of the MgF2 molecule.
a. linear, nonpolar
b. linear, polar
c. bent, nonpolar
d. bent, polar
20. There are ____ and ____ bonds respectively, in C2Cl2
a. 3 and 2
b. 3 and 4
c. 4 and 3
d. 2 and 3
e. 5 and 0
21. The sp3d hybrid orbital set contains how many orbitals?
a. 2
b. 3
c. 4
d. 5
e. 6
22. Which of the following exhibit allotropic forms?
a. hydrogen
c. sodium
b. oxygen
d. xenon
23. Which element has the largest atomic radius?
a. B
b. Al c. Ga d. In
e. Tl
24. Which atom has the largest ionization energy?
a. Li
b. B
c. C
d. N
e. Ne
25. What is the mass in grams of 4.25 x 1020 molecules of H2O?
a. 0.127 g
b. 0.0127 g
c. 1420 g
d. 142 g e. 4.25 x 1020 g
26. What is the weight percentage of Al in Al2O3?
a. 26.46%
b. 20.93%
c. 52.92%
d. 47.08%
e. 53.21%
27. 0.600 mol of a substance weighs 62.5 g. How many moles of it are there in 100.06?
a. 1.04 mol
b. 0.96 mol
c. 0.0096 mol d. 0.104 mol
e. 0.600 mol
28. How many grams of KCl (molar mass = 74.6 g/mol) are contained in 500 mL of a 0.250 M KCl
aqueous solution?
a. 0.125
b. 9.33
c. 125
d. 9330
29. A 300 mL solution of 3.0 M HCl is diluted to 2.0 L. What is the final molarity?
a. 0.45 M
b. 450 M
c. 20 M
d. 0.05 M
e. 0.50 M
30. How much heat is required to convert 100 g of water at 40C to water vapor at 100C? The eat
capacity of water is 4.184 J/gC, and the heat required to vaporize water is 2.26 kJ/g.
a. 227 kJ
b. 418 kJ
c. 226 kJ
d. 25.1 kJ
e. 251 kJ
31. Given the chemical equation:
S(s) + O2(g)  SO2(g)
H = -297.1 kJ/mol
How much heat is associated with the burning of 4.00 g of sulfur?
a. -586 kJ
b. 36.4 kJ
c. 293 kJ
d. -36.4 kJ
e. -293 kJ
32. Which of the following has a standard heat of formation 0 kJ/mol at 25C and standard atmospheric
pressure?
a. H2O(l)
b. O2(g)
c. Fe(l)
d. HCl(l)
e. SiO2(s)
33. Which of the following is an ionic compound?
a. CO2
b. PCl3
c. NO2
d. BaCl2
34. Which of the following metals cannot displace hydrogen from water?
a. Mg
b. Ba
c. Li
d. Ag
35. Copper does not react with hydrochloric acid whereas manganese does? This means that
a. copper is more active than hydrogen
b. manganese is less active than hydrogen
c. chloride ion will react with copper
d. manganese is higher on the activity series than copper
36. What is the E for a system when it does 230 kJ of work on its surroundings and 130 kJ of heat is
removed from the system?
a. +100 kJ
b. -100 kJ
c. -360 kJ
d. -360 kJ
37. How many electrons are there in the outermost shell of arsenic?
a. 3
b. 4
c. 5
d. 6
e. 7
38. Element M reacts with oxygen to produce a pure sample of MO 2. Find the atomic weight and the
identity of M if 9.6 g of oxygen reacts with 16.5 g of M to produce 26.1 g of MO 2.
a. 12 (C)
b. 14 (N)
c. 32 (S)
d. 28 (Si)
e. 55 (Mn)
39. Octane (C8H18, MW=114.08) is burned completely in an excess of air to give carbon dioxide and water
vapor. How many grams of carbon dioxide can be produced by the complete combustion of 28.52 g of
octane?
a. 11.0 g
b. 22.0 g
c. 44.0 g
d. 88.0 g
e. 176.0 g
40. What is the density in grams per liter of Ne gas at STP conditions?
a. 1.000 g/L
b. 0.9009 g/L
c. 1.097 g/L
d. 0.0971 g/L
e. not enough information
41. 43.2 g of a gas occupies 22.4 L at 200C and 2.00 atm. What is the molar mass?
a. 49.9 g/mol
c. 21.6 g/mol
b. 37.4 g/mol
d. 13.2 g/mol
42. A real gas typically exhibits behavior that is closest to an ideal gas at
a. low pressure and high temperature
c. low pressure and low temperature
b. high pressure and high temperature
d. low pressure and high temperature
43. The number of valence shell electrons for oxygen is
a. 2
b. 4
c. 6
d. 8
44. Which of the following is not allowed?
a. 2s
b. 2f
c. 3p d. 4d
45. What are the possible values of ml for l = 3?
a. 3, -3
c. 3, 2, 1, -1, -2, -3
b. 3, 0, 3
d. 3, 2, 1, 0, -1, -2, -3
46. As the principal quantum number of the Bohr orbit increases, the energy levels of a hydrogen atom
a. becomes the same
c. are further apart
b. are closer together
d. approach an infinitely negative energy
47. What is the frequency of ultraviolet radiation with a wavelength of 15.3 nm?
a. 1.96 x 10^16/s c. 4.59/s
b. 1.96 x 10^7/s
d. 4.59 x 10^-9/s
48. Which one of the following possess delocalized  electrons?
a. CH2Cl2
b. BrCN
c. N2O
d. a and b
e. b and c
49. Which of the following ionic crystals would you expect to have the largest lattice energy?
a. LiCl
b. LiBr
c. CaO
d. SrO
e. BaSO4
50. The value of H for the following reaction is -186 kJ. Calculate the value of Hf (in kJ/mol)
for HCl (g)
H2 (g) + Cl2 (g)  2HCl (g)
a. -372
b. -127
c. -93.0
d. -186
6. A sample of gas is to be identified by means of its behavior in the presence of a glowing splint. Which
gas will neither itself burn
nor cause the splint to burn?
(A) oxygen
(B) nitrogen
(C) hydrogen
(D) methane
7. A compound prepared as a model of hemoglobin is 4.6% iron by mass. If the compound is known to
contain a single iron atom, which of these values will be closest to its molar mass?
(A) 1000 g mol¯1
(B) 1200 g mol¯1
(C) 1400 g mol¯1
(D) 1600 g mol¯1
8. How many hydrogen atoms are present in 0.046g of ethanol, C2H5OH? (Molar Mass of C2H5OH is 46 g
mol¯1)
(A) 6.0 x 1020
(B) 1.2 x 1021
(C) 3.0 x 1021
(D) 3.6 x 1021
9. Which of these hydrated salts contains the greatest percentage of water by mass?
(A) BaCl2 · 2H2O
(B) CuSO4 · 5H2O
(C) CaCl2 · 6H2O
(D) Ni(ClO4)2 · 6H2O
11. What volume of 0.15 M HCl can be made from 7.5 mL of concentrated HCl (12M)?
(A) 0.060 L
(B) 0.60 L
(C) 6.0 L
(D) 6.0 x 102 L
12. Hematite, Fe2O3, is the most common iron ore. How many moles of hematite are in an ore sample that
contains 355 g of iron?
Assume hematite is the only source of iron in this ore.
(A) 1.11 mol
(B) 1059 mol
(C) 3.18 mol
(D) 6.36 mol
14. A 2.0 mL sample of HCl(g) is mixed with a 1.5 mL of NH3(g). What is the volume if the resulting
mixture after the reaction is
complete? (Assume all measurements are carried out at the same pressure and temperature and that the
volume of the solid is
negligible)
HCl(g) + NH3(g) ---> NH4Cl(s)
(A) 0.5 mL
(B) 1.5 mL
(C) 2.0 mL
(D) 3.5 mL
15. A student wants to prepare 250. mL of 0.10 M NaCl solution. Which procedure is most appropriate?
(The molar mass of NaCl
is 58.4 g mol¯1)
(A) Add 5.84 g of NaCl to 250. mL of H2O
(B) Add 1.46 g of NaCl to 250. mL of H2O
(C) Dissolve 5.84 g of NaCl in 50 mL of H2O and dilute to 250. mL.
(D) Dissolve 1.46 g of NaCl in 50 mL of H2O and dilute to 250. mL.
16. Which set of temperature and pressure conditions will cause a gas to exhibit the greatest deviation from
ideal gas behavior?
(A) 100 °C and 4 atm
(B) 100 °C and 2 atm
(C) -100 °C and 4 atm
(D) 0 °C and 2 atm
17. A mixture of 0.5 mol of CH4, 0.5 mol of H2 and 0.5 mole of SO2 is introduced into a 10.0 L container
at 25 °C. If the container has a pinhole leak, which describes the relationship between the partial pressures
of the individual components in the container after 3 hours?
(A) PSO2 > PCH4 > PH2
(B) PSO2 < PCH4 < PH2
(C) PSO2 < PCH4 > PH2
(D) PSO2 = PCH4 = PH2
22. Carbon reacts with oxygen according to this equation.
2C(s) + O2(g) ---> 2CO(g)
H = -220 kJ
Which statements are true?
1. The reaction is exothermic.
2. The combustion of 0.50 mol of carbon produces 55 kJ of heat energy
(A) 1 only
(B) 2 only
(C) both 1 and 2
(D) neither 1 nor 2
24.
Reaction
H°, kJ mol¯1
(1/2) N2(g) + (1/2) O2(g) ---> NO(g)
90.2 kJ mol¯1
(1/2) N2(g) + O2(g) ---> NO2(g)
33.2 kJ mol¯1
Use these data to calculate H° for this reaction.
NO(g) + (1/2) O2(g) ---> NO2(g)
(A) -57.0
(B) -28.5
(C) +28.5
(D) +57.0
26. How many grams of benzene, C6H6(l), must be burned in a bomb calorimeter to raise its temperature
by 1.5 °C? Given: The calorimeter constant is 12.59 kJ C¯1 and the H°:
combustion for C6H6 = -491 kJ g¯1
(A) 0.45 g
(B) 2.8 g
(C) 3.3 g
(D) 8.4 g
44. What is the total number of p orbitals completely or partially filled in a gaseous silicon atom in its
ground state?
(A) 1
(B) 2
(C) 4
(D) 5
45. What is the electron configuration of the Co3+ ion?
(A) 1s2 2s22p6 3s23p63d6
(B) 1s2 2s22p6 3s23p63d4 4s2
(C) 1s2 2s22p6 3s23p63d5 4s1
(D) 1s2 2s22p6 3s23p63d7 4s2
46. For which element is the "last electron" added to a d orbital?
(A) Ba
(B) Nd
(C) Hf
(D) Pb
47. When the species F¯, Na+, and Ne are arranged in order of increasing energy for the removal of an
electron, what is the correct order?
(A) F¯ < Na+ < Ne
(B) F¯ < Ne < Na+
(C) Na+ < Ne < F¯
(D) Ne < F¯ < Na+
48. Which electronic transition in a hydrogen atom occurs with an energy that corresponds to visible light?
(A) n = 2 ---> n = 1
(B) n = 5 ---> n = 1
(C) n = 4 ---> n = 2
(D) n = 6 ---> n = 3
49. Which species has a Lewis electron structure with one, and only one, unshared pair of valence
electrons?
(A) NH2¯
(B) H3O+
(C) H2S
(D) CH4
50. Which compound is expected to have the lowest melting point?
(A) CsF
(B) RbF
(C) KF
(D) NaF
51. Which of these molecules does not contain two pi bonds?
(A) CO
(B) CS2
(C) H2CCO
(D) H2CCH2
52. Which arrangement shows the bonds H-H, C-C, and Si-Si in order of increasing bond energy?
(A) Si-Si < C-C < H-H
(B) C-C < H-H < Si-Si
(C) H-H < Si-Si < C-C
(D) H-H < C-C < Si-Si
53. Which of the following is not a possible electron configuration for an atom, possibly in an excited
(higher energy) state?
a. 1s22s22p2
b. 1s22s22p3
c. 1s22s32p
d. 1s22s22p3
54. The order in which electrons are assigned to orbitals is (< means “comes before”)
a. 1s < 2s <2p < 3s < 3p < 3d < 4s…
b. 1s <2s < 2p < 3s < 3p <4s < 3d…
c. 1s < 2s < 3s < 4s < 2p < 3p < 3d…
d. 1s < 1p < 2s < 2p < 2d < 3s <3p…
55. The electron configuration for Cu (in the ground state) is
a. [Ar]3d104s1
b. [Ar]3d94s2
c. [Ar]3d83s2
d. [Ar]3d104s2
56. The largest of the atoms Mg, Cl, Sr, I is
a. Mg
b. Cl
c. Sr
d. I
57. The most electronegative of the elements Mg, Cl, Sr, I is
a. Mg
b. Cl
c. Sr
d. I
58. The number of valence electrons in the P atom is
a. 3
b. 5
c. 15
d. 31
59. In the Lewis model a chemical bond is provided by
a. An electron pair in a bonding orbital
b. Electrons with opposite spins
c. Any electron pair
d. A shared electron pair
60. Which of the following statements about formal charge is correct?
a. Formal charges are an accurate description of the actual electron distribution in a
molecule or ion.
b. Formal charges should not occur in a correct Lewis structure.
c. Formal charges can be avoided by expansion of the valence shell.
d. The sum of the formal charges is equal to the total charge on the molecule or ion.
61. Which of the following molecules should be expected to have the largest dipole moment?
a. N2
b. LiCl
c. CO
d. CO2
62. The hybridization on the N atom is NH3 is
a. Pure s
b. Sp
c. Sp2
d. Sp3
63. Which of the following molecules includes a pi bond (or bonds)?
a. H2
b. CH3Cl
c. O2
d. C2H6
64. Write the atomic orbital electron configuration for Si.
65. Write the Lewis dot structure for the CO2 molcule.
66. Write the appropriate Lewis dot structure or structures for the carbonate anion, CO 23-. Give the
formal charge for each atom.
67. Use the VSEPR model to predict the geometry of CO2.
68. A water sample is found to contain 1.2 micrograms of Pb per liter. This can also be stated as
a.
b.
c.
d.
1.2 miligrams per mililiter
1.2 grams per microliter
1.2 miligrams per kiloliter
1.2 kilograms per liter
69. Which of the following numbers has three significant figures?
a. 1.00
b. .00345
c. 678,000
d. they all do
70. Which of the following is not a necessary component of a neutral atom?
a. One or more electrons
b. One or more protons
c. One or more neutrons
d. A nucleus
71. Which of the following is a true statement?
a. Acetylene, HCCH, and benzene, C2H6 have the same empirical formula.
b. Acetylene, HCCH, and benzene, C2C6 have the same molecular formula.
c. Ethanol, C2H5OH, and dimethyl ether, CH3OCH3, have different molecular formulas.
d. Ethanol, C2H5OH, and dimethyl ether, CH3OCH3, have the same structural formula.
72. Which of the following compounds has the greatest weight percentage of oxygen?
a. C2H5OH
b. NaOH
c. CH3COOH
d. SO2
73. Zinc compounds include zinc sulfate, zinc sulfide, and zinc sulfite. Which list of formulas is
correct for these compounds in the order listed above?
a. ZnSO4, ZnS, ZnSO3
b. ZnSO4, ZnSO3, ZnS
c. ZnS, ZnSO3, ZnSO4
d. ZnS, Zn2S, Zn3S
74. How many hydrogen atoms are there in a mole of water?
75. Write the chemical formula for copper (II) chloride and give the name of NaNO 3.