Exam 1 CHM Flashcards
(144 cards)
1
Q
Pentane, C5H12, boils at 35°C. Which of the following is true about kinetic energy, Ek, and potential energy, Ep, when liquid pentane at 35°C is compared with pentane vapor at 35°C? A) Ek(g) Ep(l); Ek(g) ≈ Ek(l) B) Ek(g) > Ek(l); Ep(g) ≈ Ep(l) E) Ep(g) ≈ Ep(l); Ek(g) ≈ Ek(l) C) Ep(g) Ep(l); Ek(g) ≈ Ek(l)
A
Ep(g)
2
Q
Which of the following is true about kinetic energy, Ek, and potential energy, Ep, when ethyl alcohol at 40°C is compared with ethyl alcohol at 20°C? A) Ek(40°C) Ek(20°C); Ep(40°C) ≈ Ep(20°C) C) Ep(40°C) Ep(20°C); Ek(40°C) ≈ Ek(20°C) E) Ep(40°C) > Ep(20°C); Ek(40°C) > Ek(20°C)
A
Ek(40°C) > Ek(20°C); Ep(40°C) ≈ Ep(20°C)
3
Q
A sample of octane in equilibrium with its vapor in a closed 1.0-L container has a vapor pressure of 50.0 torr at 45°C. The container’s volume is increased to 2.0 L at constant temperature and the liquid/vapor equilibrium is reestablished. What is the vapor pressure?
A)
> 50.0 torr
B)
50.0 torr
C)
25.0 torr
D)
The mass of the octane vapor is needed to calculate the vapor pressure.
E)
The external pressure is needed to calculate the vapor pressure.
A
50.0 torr
4
Q
Which one of the following quantities is generally not obtainable from a single heating or cooling curve of a substance, measured at atmospheric pressure? A) melting point D) heat of fusion B) boiling point E) heat of vaporization C) triple point
A
triple point
5
Q
The phase diagram for xenon has a solid-liquid curve with a positive slope. Which of the following is true?
A)
Solid xenon has a higher density than liquid xenon.
B)
Solid xenon has the same density as liquid xenon.
C)
The phase diagram cannot be used to predict which phase of xenon is denser.
D)
Freezing xenon is an endothermic process.
E)
None of the above statements is true.
A
Solid xenon has a higher density than liquid xenon.
6
Q
Liquid ammonia (boiling point = –33.4°C) can be used as a refrigerant and heat transfer fluid. How much energy is needed to heat 25.0 g of NH3(l) from –65.0°C to –12.0°C? Specific heat capacity, NH3(l): 4.7 J/(g⋅K) Specific heat capacity, NH3(g): 2.2 J/(g⋅K) Heat of vaporization: 23.5 kJ/mol Molar mass, : 17.0 g/mol A) 5.5 kJ B) 6.3 kJ C) 39 kJ D) 340 kJ E) 590 kJ
A
39 kJ
7
Q
Diethyl ether, used as a solvent for extraction of organic compounds from aqueous solutions, has a high vapor pressure which makes it a potential fire hazard in laboratories in which it is used. How much energy is released when 100.0 g is cooled from 53.0°C to 10.0°C? Boiling point: 34.5°C Heat of vaporization: 351 J/g Specific heat capacity, (CH3)2O(l): 3.74 J/(g⋅K) Specific heat capacity, (CH3)2O(g): 2.35 J/(g⋅K) A) 10.1 kJ B) 13.1 kJ C) 16.1 kJ D) 45.2 kJ E) 48.6 kJ
A
-48.6 kJ
8
Q
A 5.00 g sample of water vapor, initially at 155°C is cooled at atmospheric pressure, producing ice at –55°C. Calculate the amount of heat energy lost by the water sample in this process, in kJ. Use the following data: specific heat capacity of ice is 2.09 J/g⋅K; specific heat capacity of liquid water is 4.18 J/g⋅K; specific heat capacity of water vapor is 1.84 J/g⋅K; heat of fusion of ice is 336 J/g; heat of vaporization of water is 2260 J/g.
A) 15.6 kJ B) 10.2 kJ C) 5.4 kJ D) 16.2 kJ E) 1.6 kJ
A
16.2 kJ
9
Q
Octane has a vapor pressure of 40. torr at 45.1°C and 400. torr at 104.0°C. What is its heat of vaporization? A) 39.0 kJ/mol D) 710 kJ/mol B) 46.0 kJ/mol E) none of the above C) 590 kJ/mol
A
39.0 kJ/mol
10
Q
Liquid sodium can be used as a heat transfer fluid. Its vapor pressure is 40.0 torr at 633°C and 400.0 torr at 823°C. Calculate its heat of vaporization. A) 43.4 kJ/mol D) 1.00 × 10^2 kJ/mol B) 52.5 kJ/mol E) none of the above C) 70.6 kJ/mol
A
1.00 x 10^2 kj/Mol
11
Q
The Clausius-Clapeyron equation is used in calculations of A) melting and freezing points. B) vapor pressures of liquids. C) osmotic pressures of solutions. D) heats of vaporization at different temperatures. E) crystal structure.
A
vapor pressure of liquids
12
Q
The normal boiling point of ether is 307.8 K. Calculate the temperature at which its vapor pressure is exactly half of that at its normal boiling point. The heat of vaporization for ether is 26.69 kJ/mol.
A) 305 K B) 302 K C) 295 K D) 289 K E) 281 K
A
289 K
13
Q
Neon atoms are attracted to each other by A) dipole-dipole forces. D) covalent bonding. B) London dispersion forces. E) intramolecular forces. C) hydrogen bonding.
A
London dispersion
14
Q
Ammonia's unusually high melting point is the result of A) dipole-dipole forces. D) covalent bonding. B) London dispersion forces. E) ionic bonding. C) hydrogen bonding.
A
hydrogen bonding
15
Q
Octane is a component of fuel used in internal combustion engines. The dominant intermolecular forces in octane are A) dipole-dipole forces. D) covalent bonds. B) London dispersion forces. E) carbon-hydrogen bonds. C) hydrogen bonding.
A
London dispersion
16
Q
In hydrogen iodide \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ are the most important intermolecular forces. A) dipole-dipole forces D) covalent bonds B) London dispersion forces E) polar covalent bonds C) hydrogen bonding
A
dipole-dipole
17
Q
When the electron cloud of a molecule is easily distorted, the molecule has a high \_\_\_\_\_\_\_\_\_\_\_\_\_. A) polarity D) van der Waals radius B) polarizability E) compressibility C) dipole moment
A
polarizability
18
Q
Which of the following atoms should have the greatest polarizability?
A) F B) Br C) Po D) Pb E) He
A
Pb
19
Q
Which of the following atoms should have the smallest polarizability?
A) Si B) S C) Te D) Bi E) Br
A
S
20
Q
The strongest intermolecular interactions between pentane (C5H12) molecules arise from A) dipole-dipole forces. D) ion-dipole interactions. B) London dispersion forces. E) carbon-carbon bonds. C) hydrogen bonding.
A
london-dispersion
21
Q
What types of forces exist between molecules of CO2? A) hydrogen bonding only. B) hydrogen bonding and dispersion forces. C) dipole-dipole forces only. D) dipole-dipole and dispersion forces. E) dispersion forces only.
A
dispersion forces only
22
Q
The strongest intermolecular interactions between ethyl alcohol (CH3CH2OH) molecules arise from A) dipole-dipole forces. D) ion-dipole interactions. B) London dispersion forces. E) carbon-oxygen bonds. C) hydrogen bonding.
A
hydrogen bonding
23
Q
The strongest intermolecular interactions between hydrogen sulfide (H2S) molecules arise from A) dipole-dipole forces. D) ion-dipole interactions. B) London dispersion forces. E) disulfide linkages. C) hydrogen bonding.
A
dipole-dipole
24
Q
The strongest intermolecular interactions between hydrogen fluoride (HF) molecules arise from A) dipole-dipole forces. D) ion-dipole interactions. B) London dispersion forces. E) ionic bonds. C) hydrogen bonding.
A
hydrogen bonding
25
Which one of the following substances will have hydrogen bonds between molecules?
A) (CH3)3N B) CH3–O–CH3 C) CH3CH2–OH D) CH3CH2–F E) HI
CH3CH2–OH
26
```
Which of the following pairs of molecules can form hydrogen bonds between them?
A)
HCl and HI
D)
SO2 and CH2O
B)
CH3OH and NH3
E)
H2 and O2
C)
CH4 and H2O
```
CH3OH and NH3
27
Which of the following pairs is arranged with the particle of higher polarizability listed first?
A) Se2–, S2– B) I, I– C) Mg2+, Mg D) Br, I E) none of the above
Se2–, S2–
28
```
Which of the following pairs is arranged with the particle of higher polarizability listed first?
A)
CCl4, CI4
D)
NH3, NF3
B)
H2O, H2Se
E)
none of the above
C)
C6H14, C4H10
```
C6H14, C4H10
29
Which of the following should have the highest boiling point?
A) CF4 B) CCl4 C) CBr4 D) CI4 E) CH4
CI4
30
Which of the following should have the lowest boiling point?
| A) C5H12 B) C6H14 C) C8H18 D) C10H22 E) C12H26
C5H12
31
Which of the following has a boiling point which does not fit the general trend?
A) NH3 B) PH3 C) AsH3 D) SbH3 E) BiH3
NH3
32
```
Select the pair of substances in which the one with the higher vapor pressure at a given temperature is listed first.
A)
C7H16, C5H12
D)
CH3CH2OH, CH3–O–CH3
B)
CCl4, CBr4
E)
Xe, Kr
C)
H2O, H2S
```
CCl4, CBr4
33
```
Comparing the energies of the following intermolecular forces on a kJ/mol basis, which would normally have the highest energy (i.e., be the strongest force)?
A)
ion-induced dipole
D)
dipole-dipole
B)
dipole-induced dipole
E)
dispersion
C)
ion-dipole
```
ion-dipole
34
Which of the following should have the highest surface tension at a given temperature?
A) CH4 B) CF4 C) CCl4 D) CBr4 E) CI4
Cl4
35
```
Which of the following properties measures the energy needed to increase the surface area of a liquid?
A)
capillary action
D)
cohesion
B)
surface tension
E)
specific elasticity
C)
viscosity
```
surface tension
36
When the adhesive forces between a liquid and the walls of a capillary tube are greater than the cohesive forces within the liquid
A)
the liquid level in a capillary tube will rise above the surrounding liquid and the surface in the capillary tube will have a convex meniscus.
B)
the liquid level in a capillary tube will rise above the surrounding liquid and the surface in the capillary tube will have a concave meniscus.
C)
the liquid level in a capillary tube will drop below the surrounding liquid and the surface in the capillary tube will have a convex meniscus.
D)
the liquid level in a capillary tube will drop below the surrounding liquid and the surface in the capillary tube will have a concave meniscus.
E)
None of the above will occur.
the liquid level in a capillary tube will rise above the surrounding liquid and the surface in the capillary tube will have a concave meniscus.
37
The meniscus of mercury in a glass capillary tube is convex because of
A)
the very high density of mercury as compared with water.
B)
the low surface tension of mercury.
C)
the greater attraction of mercury atoms to the glass than to each other.
D)
the weaker attraction of mercury atoms to the glass than to each other.
E)
electrostatic repulsion between the glass and the mercury.
the greater attraction of mercury atoms to the glass than to each other.
38
```
Which of the following terms refers to the resistance of a liquid to flow?
A) surface tension
B) capillary action
C) viscosity
D) adhesion
E) cohesion
```
viscosity
39
```
Which of the following factors contributes to a low viscosity for a liquid?
A)
low temperature
D)
high molecular weight
B)
spherical molecular shape
E)
high boiling point
C)
hydrogen bonding
```
spherical molecular shape
40
Which of the following liquid substances would you expect to have the lowest surface tension?
A) Pb B) CH3OCH3 C) HOCH2CH2OH D) H2O E) CH3CH2OH
CH3OCH3
41
Which of the following liquids is likely to have the highest surface tension?
A) Br2 B) C8H18 C) CH3OCH3 D) CH3OH E) Pb
Pb
42
When identical particles pack in a simple cubic lattice, there is/are ____ particle(s) per unit cell.
A) 1 B) 2 C) 3 D) 4 E) 8
1
43
A metal with a body-centered cubic lattice will have ______ atom(s) per unit cell.
A) 1 B) 2 C) 3 D) 4 E) 9
2
44
A metal such with a face-centered cubic lattice will have ________________ atom(s) per unit cell.
A) 1 B) 2 C) 3 D) 4 E) 10
4
45
Polonium crystallizes in the simple cubic lattice. What is the coordination number for Po?
A) 3 B) 4 C) 6 D) 8 E) 12
6
46
Iron crystallizes in the body-centered cubic lattice. What is the coordination number for Fe?
A) 4 B) 6 C) 8 D) 10 E) 12
8
47
Lead crystallizes in the face-centered cubic lattice. What is the coordination number for Pb?
A) 4 B) 6 C) 8 D) 10 E) 12
12
48
Which one of the following statements about unit cells and packing in solids is incorrect?
A)
In any unit cell of a solid crystal, each face of the cell must have an opposite face which is equal and parallel to it.
B)
The faces of a unit cell must all be at angles of 90° to each other.
C)
The coordination number of atoms in a close packed metal is 12.
D)
The packing efficiency in fcc structures is higher than in bcc structures.
E)
The packing efficiency in fcc and hcp structures is the same.
The faces of a unit cell must all be at angles of 90° to each other.
49
Which of the following statements concerning a face-centered cubic unit cell and the corresponding lattice, made up of identical atoms, is incorrect?
A)
The coordination number of the atoms in the lattice is 8.
B)
The packing in this lattice is more efficient than for a body-centered cubic system.
C)
If the atoms have radius r, then the length of the cube edge is √8 × r.
D)
There are four atoms per unit cell in this type of packing.
E)
The packing efficiency in this lattice and hexagonal close packing are the same.
The coordination number of the atoms in the lattice is 8.
50
Which of the following statements about the packing of monatomic solids with different unit cells is incorrect?
A)
The coordination number of atoms in hcp and fcc structures is 12.
B)
The coordination number of atoms in simple cubic structures is 6.
C)
The coordination number of atoms in bcc structures is 8.
D)
A bcc structure has a higher packing efficiency than a simple cubic structure.
E)
A bcc structure has a higher packing efficiency than a fcc structure.
A bcc structure has a higher packing efficiency than a fcc structure.
51
A cubic unit cell has an edge length of 400. pm. The length of its body diagonal (internal diagonal) in pm is therefore
A) 512. B) 566. C) 631. D) 693. E) 724.
693
52
A certain solid metallic element has a density 7.87 g/cm3 and a molar mass of 55.85 g/mol. It crystallizes with a cubic unit cell, with an edge length of 286.7 pm. Calculate the number of atoms per unit cell.
A) 1 B) 2 C) 3 D) 4 E) 6
2
53
```
Crystal structures may be conveniently measured using
A)
X-ray diffraction.
D)
microwave spectroscopy.
B)
infrared spectroscopy.
E)
magnetic resonance imaging.
C)
ultraviolet-visible spectroscopy.
```
x-ray diffraction
54
```
Which one of the following substances does not exist in the indicated solid type?
A)
graphite - network
D)
NaCl - ionic
B)
Na - metallic
E)
diamond - network
C)
SiO2 - molecular
```
SiO2-molecular
55
When liquid bromine is cooled to form a solid, which of the following types of solid would it form?
A) atomic B) metallic C) molecular D) ionic E) covalent network
molecular
56
For the solid forms of the following elements, which one is most likely to be of the molecular type?
A) Xe B) C C) Pb D) S E) Cr
S
57
```
What adjective best describes the solid compound IF7?
A) metallic
B) amorphous
C) covalent network
D) molecular
E) ionic
```
molecular
58
The coordination number of sodium and chloride ions in the NaCl lattice, are, respectively:
A) 10 and 10 B) 8 and 8 C) 6 and 6 D) 4 and 4 E) none of the above
6 and 6
59
```
In an ionic solid MX consisting of the monatomic ions, M+ and X–, the coordination number of M+ is _______________.
A)
1
B)
2
C)
6
D)
8
E)
impossible to predict without knowing the crystal structure of MX
```
impossible to predict without knowing the crystal structure of MX
60
```
A temperature increase causes __________________ in the conductivity of a semiconductor.
A)
a decrease
B)
an increase
C)
a modulation
D)
an increase or decrease (depending on the semiconductor)
E)
no change
```
an increase
61
```
A temperature increase causes __________________ in the conductivity of a conductor.
A)
a decrease
B)
an increase
C)
an increase or decrease (depending on the conductor)
D)
a modulation
E)
no chang
```
a decrease
62
```
The energy gap between the conduction band and the valence band is large for
A)
conductors.
D)
insulators.
B)
semiconductors.
E)
alloys.
C)
superconductors.
```
insulators
63
The highest temperature at which superconductivity has been achieved is approximately
A) 4 K. B) 30 K. C) 70 K. D) 100 K. E) 130 K.
130 K
64
```
When silicon is doped with an element from group 3A(13), the device/material produced is a/an
A)
intrinsic semiconductor.
D)
p-n junction.
B)
p-type semiconductor.
E)
transistor.
C)
n-type semiconductor.
```
p-type semiconductor
65
Which of the following statements about ceramics is incorrect?
A)
Silicon carbide has a diamond-like structure.
B)
Boron nitride can exist in both diamond-like and graphite-like forms.
C)
Silicon carbide can be prepared by direct reaction of silicon and carbon.
D)
Superconducting ceramics present manufacturing difficulties owing to their brittleness.
E)
Superconducting ceramic compounds usually incorporate cobalt in a key role.
Superconducting ceramic compounds usually incorporate cobalt in a key role.
66
```
Select the type of interaction which best describes the attraction between Mg2+ ions and water molecules.
A)
dipole-dipole
D)
ion-induced dipole
B)
dipole-induced dipole
E)
ion-hydrogen bond
C)
ion-dipole
```
ion-dipole
67
Under physiological conditions, amino acids in solution carry
A)
no electrical charges.
B)
a net positive charge, due to an –NH3+ group or groups.
C)
a net negative charge, due to a –COO– group or groups.
D)
both –NH2 and –COOH groups.
E)
both –NH3+ and –COO– groups.
Both --NH3+ and --COO- groups
68
```
The shape of a protein molecule is determined completely by
A)
hydrogen bonding.
B)
ion-dipole attractions.
C)
dispersion forces.
D)
disulfide bridges.
E)
the sequence of amino acids in the chain.
```
the sequence of amino acids in the chain
69
The most abundant molecules in the cell membranes of most species are
A) proteins. B) sugars. C) phospholipids. D) fatty acids. E) steroids.
phospholipids
70
Which, if any, of the following features is common to soaps, detergents, phospholipids, and channel-forming antibiotics?
A)
They all contain fatty acids.
B)
They all contain phosphate groups.
C)
They all contain polypeptide chains.
D)
Their function depends on the dual polarity of their molecules.
E)
They have none of the above features in common.
Their function depends on the dual polarity of their molecules.
71
Consider the expression below, showing the terms which contribute to the heat of solution, ΔHsoln:
ΔHsoln = ΔHsolute + ΔHsolvent + ΔHmix
Which of the following sets correctly shows the signs (positive or negative) of the three terms on the right hand side of the equation?
A)
ΔHsolute > 0; ΔHsolvent > 0; ΔHmix > 0
D)
ΔHsolute 0
B)
ΔHsolute 0; ΔHmix 0; ΔHsolvent > 0; ΔHmix
ΔHsolute > 0; ΔHsolvent > 0; ΔHmix
72
Which of the following ions will be expected to have the most negative heat of hydration, ΔHhydr?
A) Na+ B) Cs+ C) Ca2+ D) F– E) I–
Ca2+
73
```
Which of the following sets of conditions could exist when two liquids which are completely miscible in one another are mixed?
A)
ΔHsoln > 0, entropy of system decreases
B)
ΔHsoln ≈ 0, entropy of system decreases
C)
ΔHsoln ≈ 0, entropy change of system ≈ 0
D)
ΔHsoln ≈ 0, entropy of system increases
E)
none of the above
```
ΔHsoln ≈ 0, entropy of system increases
74
If a solute dissolves in an endothermic process
A)
H bonds must exist between solvent and solute.
B)
strong ion-dipole forces must exist in the solution.
C)
the solute must be a gas.
D)
the entropy of the solution is immaterial.
E)
the entropy of the solution must be greater than that of its pure components.
the entropy of the solution must be greater than that of its pure components.
75
```
When two pure substances are mixed to form a solution
A)
heat is released.
D)
there is a decrease in entropy.
B)
heat is absorbed.
E)
entropy is conserved.
C)
there is an increase in entropy.
```
there is an increase in entropy
76
Based only on the relative lattice energies of the compounds below, which one would be expected to have the lowest solubility in water?
A) NaBr B) CaS C) NaOH D) KI E) CsCl
CaS
77
A solution of sucrose (sugar) in water is in equilibrium with solid sucrose. If more solid sucrose is now added, with stirring,
A)
the concentration of the solution will increase.
B)
the concentration of the solution will decrease.
C)
the concentration of the solution will remain the same.
D)
the volume of solution will increase.
E)
a supersaturated solution will be produced.
the concentration of the solution will remain the same.
78
```
Which of the following pairs of ions is arranged so that the ion with the smaller charge density is listed first?
A)
K+, Rb+
B)
Cl–, K+
C)
Cl–, Br–
D)
Ca2+, Ba2+
E)
None of the above pairs are arranged in this way.
```
Cl–, K+
79
```
Which of the following pairs of ions is arranged so that the ion with the larger (i.e., more negative) heat of hydration is listed first?
A)
Br–, K+
B)
Mg2+, Sr 2+
C)
Ca2+, Sc3+
D)
Na+, Li+
E)
None of the above are arranged in this way.
```
Mg2+, Sr 2+
80
```
The Henry's Law constant (k) for carbon monoxide in water at 25°C is 9.71 × 10–4 mol/(L·atm). How many grams of CO will dissolve in 1.00 L of water if the partial pressure of CO is 2.75 atm?
A)
3.53 × 10–4 g
D)
7.48 × 10–2 g
B)
2.67 × 10–3 g
E)
none of the above
C)
9.89 × 10–3 g
```
7.48x10-2 g
81
Methane has a Henry's Law constant (k) of 9.88 × 10–2 mol/(L·atm) when dissolved in benzene at 25°C. How many grams of CH4 will dissolve in 3.00 L of benzene if the partial pressure of CH4 is 1.48 atm?
A) 0.0667 g B) 0.146 g C) 2.34 g D) 4.83 g E) 7.02 g
7.02
82
Soda drinks bubble when the bottle is opened because
A)
the temperature of the soda increases.
B)
exposure to atmospheric pressure squeezes the carbon dioxide from solution.
C)
the partial pressure of carbon dioxide above the solution is reduced.
D)
atmospheric nitrogen molecules displace carbon dioxide molecules.
E)
the Henry's law constant changes due to the change in pressure.
the partial pressure of carbon dioxide above the solution is reduced
83
A saturated solution of carbon dioxide in water contains 3.00 g of CO2 when the CO2 partial pressure is 8.0 atm. What mass of CO2 will escape if the partial pressure is lowered to 3.2 atm?
A) 0.90 g B) 1.20 g C) 1.40 g D) 1.80 g E) 2.20 g
1.80 g
84
```
For a given solution, which of the following concentration values will change as temperature changes?
A)
mass percent
D)
molarity
B)
molality
E)
none of the above
C)
mole fraction
```
molarity
85
Potassium fluoride is used for frosting glass. Calculate the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution.
A) 0.304 M B) 0.349 M C) 1.35 M D) 3.29 M E) 6.01 M
6.01 M
86
Potassium hydrogen phosphate is used in the preparation of non-dairy powdered creamers. Calculate the molarity of a solution prepared by dissolving 238 g of K2HPO4 in enough water to produce 275 mL of solution.
A) 0.732 M B) 0.865 M C) 2.66 M D) 4.97 M E) none of the above
4.97
87
Calculate the molarity of a solution prepared by diluting 1.85 L of 6.5M KOH to 11.0 L.
A) 0.28 M B) 0.91 M C) 1.1 M D) 3.1 M E) 3.9 M
1.1 M
88
What volume of concentrated (14.7 M) phosphoric acid is needed to prepare 25.0 L of 3.0 M H3PO4?
A) 0.20 L B) 0.57 L C) 1.8 L D) 3.6 L E) 5.1 L
5.1 L
89
Saccharin, one of the first non-nutritive sweeteners used in soft-drinks, is 500 times sweeter than sugar in dilute aqueous solutions. The solubility of saccharin is 1.00 gram per 290 mL of solution. What is the molarity of a saturated saccharin solution?
(saccharin = 183.2 g/mol)
A) 0.0188 M B) 0.632 M C) 1.58 M D) 3.45 M E) none of the above
0.0188 M
90
Which of the following statements describes the correct method of preparation of 1.00 L of a 2.0 M urea solution? urea = 60.06 g/mol
A)
Dissolve 120 g of urea in 1.00 kg of distilled water.
B)
Dissolve 120 g of urea in 880 g of distilled water.
C)
Dissolve 120 g of urea in enough distilled water to produce 1.00 L of solution.
D)
Dissolve 120 g of urea in 1.00 liter of distilled water.
E)
The density of urea is needed in order to do this calculation.
Dissolve 120 g of urea in enough distilled water to produce 1.00 L of solution
91
Copper(II) bromide is used as a wood preservative. What mass of CuBr2 is needed to prepare 750.0 mL of a 1.25 M solution?
A) 134 g B) 209 g C) 372 g D) 938 g E) > 1 kg
209 g
92
What is the molality of a solution prepared by dissolving 86.9 g of diethyl ether, C4H10O, in 425 g of benzene, C6H6?
A) 0.362 m B) 0.498 m C) 2.01 m D) 2.76 m E) none of the above
2.76 m
93
Calcium nitrite is used as a corrosion inhibitor in lubricants. What is the molality of a solution prepared by dissolving 18.5 g of calcium nitrite in 83.5 g of distilled water?
A) 0.0342 m B) 0.0855 m C) 0.222 m D) 0.444 m E) 1.68 m
1.68 m
94
```
Cadmium bromide is used in photography and lithography. Calculate the molality of a solution prepared by dissolving 45.38 g of CdBr2 in 375.0 g of water.
A)
0.03035 m
D)
0.4446 m
B)
0.01600 m
E)
none of the above
C)
0.1210 m
```
0.4446 m
95
Isoamyl salicylate ( = 208.25 g/mol) has a pleasant aroma and is used in perfumes and soaps. Which of the following combinations gives a 0.75 m solution of isoamyl salicylate in ethyl alcohol (d = 0.7893 g/mL)?
A)
117.2 g isoamyl salicylate in 950.0 mL of ethyl alcohol
B)
117.2 g isoamyl salicylate in 750.0 mL of ethyl alcohol
C)
117.2 g isoamyl salicylate in 750.0 mL of solution
D)
117.2 g isoamyl salicylate in 592.0 g of ethyl alcohol
E)
none of the above
117.2 g isoamyl salicylate in 950.0 mL of ethyl alcohol
96
The chemist, Anna Lytic, must prepare 1.00 kg of 15.0% (w/w) acetic acid using a stock solution which is 36.0% (w/w) acetic acid (d = 1.045 g/mL). Which of the following combinations will give her the solution she wants?
A)
417 mL of 36% acetic acid in 583 mL of distilled water
B)
417 g of 36% acetic acid in 583 g of distilled water
C)
360 mL of 36% acetic acid in 640 mL of distilled water
D)
360 g of 36% acetic acid in 640 g of distilled water
E)
150 g of 36% acetic acid in 850 g of distilled water
417 g of 36% acetic acid in 583 g of distilled water
97
The solubility of the oxidizing agent potassium permanganate is 7.1 g per 100.0 g of water at 25°C. What is the mole fraction of potassium permanganate in this solution?
A) 0.0080 B) 0.0086 C) 0.066 D) 0.45 E) 0.48
0.0080
98
What is the mole fraction of Ar in a mixture containing 10.1 g of Ne, 79.9 g of Ar, and 83.8 g of Kr?
A) 0.40 B) 0.25 C) 0.20 D) 0.14 E) 0.058
0.14
99
A solution of ethanol (C2H6O) in water is sometimes used as a disinfectant. 1.00 L of this solution contains 553 g of ethanol and 335 g of water. What is the mole fraction of ethanol in this solution?
A) 0.377 B) 0.392 C) 0.553 D) 0.608 E) 0.623
0.392
100
A solution of ethanol (C2H6O) in water is sometimes used as a disinfectant. 1.00 L of this solution contains 553 g of ethanol and 335 g of water. What is the molality of the ethanol in this solution?
A) 0.392 m B) 0.608 m C) 13.5 m D) 33.6 m E) 35.8 m
35.8 m
101
Aqueous ammonia is commercially available in a solution that is 28% (w/w) ammonia. What is the mole fraction of ammonia in such a solution?
A) 0.017 B) 0.023 C) 0.012 D) 0.24 E) 0.29
0.29
102
Sodium hydroxide is a common ingredient in drain cleaners such as Drano. The mole fraction of sodium hydroxide in a saturated aqueous solution is 0.310. What is the molality of the solution?
A) 0.310 m B) 0.690 m C) 1.24 m D) 12.4 m E) 25.0 m
12.4 m
103
The mole fraction of potassium nitrate in an aqueous solution is 0.0194. The solution's density is 1.0627 g/mL. Calculate the molarity of the solution.
A) 0.0194 M B) 0.981 M C) 1.05 M D) 1.96 M E) 19.4 M
1.05 M
104
A 0.89% (w/v) sodium chloride solution is referred to as physiological saline solution because it has the same concentration of salts as human blood. What is the molarity of a physiological saline solution?
A) 0.0028 M B) 0.015 M C) 0.15 M D) 0.30 M E) 0.35 M
0.15 M
105
A 2.0% (w/v) solution of sodium hydrogen citrate, Na2C6H6O7, which also contains 2.5% (w/v) of dextrose, C6H12O6, is used as an anticoagulant for blood which is to be used for transfusions. What is the molarity of the sodium hydrogen citrate in the solution?
A) 0.085 M B) 0.19 M C) 0.53 M D) 1.2 M E) 1.3 M
0.085 M
106
```
Procaine hydrochloride ( = 272.77 g/mol) is used as a local anesthetic. Calculate the molarity of a 4.666 m solution which has a density of 1.1066 g/mL.
A) 2.272 M
B) 4.056 M
C) 4.216 M
D) 4.666 M
E) none of the above
```
2.272 M
107
```
The concentration of iodine in sea water is 60. parts per billion by mass. If one assumes that the iodine exists in the form of iodide anions, what is the molarity of iodide in sea water? (The density of sea water is 1.025 g/mL.)
A)
4.8 × 10–13 M
D)
4.7 × 10–4 M
B)
4.8 × 10–10 M
E)
4.7 × 10–1 M
C)
4.8 × 10–7 M
```
4.8 x 10-7 M
108
```
Children under the age of six with more than 0.10 ppm of lead in their blood can suffer a reduction in I.Q. or have behavior problems. What is the molality of a solution which contains 0.10 ppm of lead?
A)
4.8 × 10–10 m
D)
4.8 × 10–1 m
B)
4.8 × 10–7 m
E)
none of the above
C)
4.8 × 10–4 m
```
4.8 x 10-7
109
```
Colligative properties depend on
A)
the chemical properties of the solute.
D)
the molar mass of the solute.
B)
the chemical properties of the solvent.
E)
the number of particles dissolved.
C)
the masses of the individual ions.
```
the number of particles dissolved.
110
Raoult's Law relates the vapor pressure of the solvent above the solution to its mole fraction in the solution. Which of the following is an accurate statement?
A)
Raoult's Law applies exactly to all solutions.
B)
Raoult's Law works best when applied to concentrated solutions.
C)
Raoult's Law works best when applied to dilute solutions.
D)
Raoult's Law applies only to non-ideal solutions.
E)
None of the above statements is accurate.
Raoult's Law works best when applied to dilute solutions.
111
The vapor pressure of pure acetone (propanone) is 266 torr. When a non-volatile solute is added, the vapor pressure of acetone above the solution falls to 232 torr. What is the mole fraction of the non-volatile solute in the solution?
A) 0.87 B) 0.69 C) 0.32 D) 0.13 E) 0.045
0.13
112
The vapor pressure of pure acetone (propanone) is 266 torr. When a non-volatile solute is added, the vapor pressure of acetone above the solution falls to 232 torr. What is the mole fraction of acetone in the solution?
A) 0.87 B) 0.69 C) 0.32 D) 0.13 E) 0.045
0.87
113
```
From the following list of aqueous solutions and water, select the one with the highest boiling point.
A)
1.0 m KNO3
D)
2.0 m C12H22O11 (sucrose)
B)
0.75 m NaCl
E)
pure water
C)
0.75 m CuCl2
```
0.75 m CuCl2
114
What concentration of aqueous FeCl3 would have the same osmotic pressure as a 0.20 M solution of CaCl2 at the same temperature, assuming ideal behavior?
A) 0.60 M B) 0.40 M C) 0.30 M D) 0.15 M E) 0.10 M
0.15 M
115
```
From the following list of aqueous solutions and water, select the one with the lowest freezing point.
A)
0.75 m (NH4)3PO4
D)
1.5 m CH3OH, methyl alcohol
B)
1.0 m CaSO4
E)
pure water
C)
1.0 m LiClO4
```
0.75 m (NH4)3PO4
116
```
Which of the following aqueous solutions should demonstrate the most ideal behavior?
A)
0.1 M K2SO4
D)
0.1 M MgSO4
B)
0.1 M CaCl2
E)
0.1 M NaCl
C)
3.0 M LiF
```
0.1 M NaCl
117
```
Which of the following aqueous solutions should demonstrate the most non-ideal behavior?
A)
0.1 M NaI
D)
2.0 M CuCl2
B)
0.2 M CuSO4
E)
2.0 M CsCl
C)
0.5 M KBr
```
2.0 M CuCl2
118
```
Select the strongest electrolyte from the following set.
A) CH3CH2OH, ethanol
B) LiNO3
C) C6H12O6, glucose
D) CCl4
E) HF
```
LiNO3
119
```
Select the weakest electrolyte from the following set.
A)
Na2SO4
D)
CaCl2
B)
KCl
E)
LiOH
C)
CH3CH2COOH, propionic acid
```
CH3CH2COOH, propionic acid
120
How many moles of sulfate ions are present in 1.0 L of 0.5 M Li2SO4?
A) 0.5 mol B) 1.0 mol C) 1.5 mol D) 2.0 mol E) 3.0 mol
0.5 mol
121
```
How many moles of bromide ions are present in 750.0 mL of 1.35 M MgBr2?
A) 0.506 mol
B) 1.01 mol
C) 2.03 mol
D) 3.04 mol
E) none of the above
```
2.03 mol
122
How many moles of solute particles are present in 100.0 mL of 2.50 M (NH4)3PO4?
A) 0.100 mol B) 0.250 mol C) 0.500 mol D) 0.750 mol E) l.00 mol
1.00 mol
123
Two aqueous are prepared: 1.00 m Na2CO3 and 1.00 m LiCl. Which of the following statements is true?
A)
The Na2CO3 solution has a higher osmotic pressure and higher vapor pressure than the LiCl solution.
B)
The Na2CO3 solution has a higher osmotic pressure and higher boiling point than the LiCl solution.
C)
The Na2CO3 solution has a lower osmotic pressure and lower vapor pressure than the LiCI solution.
D)
The Na2CO3 solution has a lower osmotic pressure and higher boiling point than the LiCl solution.
E)
None of the above statements is true.
The Na2CO3 solution has a higher osmotic pressure and higher boiling point than the LiCl solution.
124
Two aqueous solutions are prepared: 2.0 m Cu(NO3)2 and 2.0 m NaBr. Which of the following statements is true?
A)
The Cu(NO3)2 solution has a higher vapor pressure and lower freezing point than the NaBr solution.
B)
The Cu(NO3)2 solution has a higher vapor pressure and higher freezing point than the NaBr solution.
C)
The Cu(NO3)2 solution has a lower vapor pressure and lower freezing point than the NaBr solution.
D)
The Cu(NO3)2 solution has a lower vapor pressure and higher freezing point than the NaBr solution.
E)
None of the above statements is true
The Cu(NO3)2 solution has a lower vapor pressure and lower freezing point than the NaBr solution.
125
```
Which of the following aqueous solutions will have the lowest osmotic pressure?
A)
0.10 m KOH
D)
0.05 m BaCl2
B)
0.10 m RbCl
E)
0.10 m K2SO4
C)
0.05 m CaSO4
```
0.05 m CaSO4
126
```
Which of the following aqueous liquids will have the lowest freezing point?
A)
0.5 m C12H22O11 (sucrose)
D)
0.5 m Li3PO4
B)
0.5 m Ca(NO3)2
E)
pure water
C)
0.5 m NiSO4
```
0.5 m Li3PO4
127
Calculate the vapor pressure of a solution prepared by dissolving 0.500 mol of a non-volatile solute in 275 g of hexane ( = 86.18 g/mol) at 49.6°C. P°hexane = 400.0 torr at 49.6°C.
A) 54 torr B) 154 torr C) 246 torr D) 346 torr E) 400. torr
346 torr
128
Safrole is used as a topical antiseptic. Calculate the vapor pressure of a solution prepared by dissolving 0.75 mol of safrole in 950 g of ethanol ( = 46.07 g/mol). P°ethanol = 50.0 torr at 25°C.
A) 1.8 torr B) 11 torr C) 15 torr D) 40 torr E) 48 torr
48 torr
129
Diethyl ether has a vapor pressure of 400.0 torr at 18°C. When a sample of benzoic acid is dissolved in ether, the vapor pressure of the solution is 342 torr. What is the mole fraction of benzoic acid in the solution?
A) 0.0169 B) 0.0197 C) 0.145 D) 0.855 E) none of the above
0.145
130
Determine the freezing point of a solution which contains 0.31 mol of sucrose in 175 g of water. Kf = 1.86°C/m
A) 3.3°C B) 1.1°C C) 0.0°C D) –1.1°C E) –3.3°C
-3.3˚C
131
Benzaldehyde ( = 106.1 g/mol), also known as oil of almonds, is used in the manufacture of dyes and perfumes and in flavorings. What would be the freezing point of a solution prepared by dissolving 75.00 g of benzaldehyde in 850.0 g of ethanol? Kf = 1.99°C/m, freezing point of pure ethanol = –117.3°C.
A) –117.5°C B) –118.7°C C) –119.0°C D) –120.6°C E)
-119.0˚C
132
Carbon tetrachloride, once widely used in fire extinguishers and as a dry cleaning fluid, has been found to cause liver damage to those exposed to its vapors over long periods of time. What is the boiling point of a solution prepared by dissolving 375 g of sulfur (S8, = 256.5 g/mol) in 1250 g of CCl4? Kb = 5.05°C/m, boiling point of pure CCl4 = 76.7°C?
A) 70.8°C B) 75.2°C C) 78.2°C D) 82.6°C E) >85°C
82.6˚C
133
Barbiturates are synthetic drugs used as sedatives and hypnotics. Barbital ( = 184.2 g/mol) is one of the simplest of these drugs. What is the boiling point of a solution prepared by dissolving 42.5 g of barbital in 825 g of acetic acid?
Kb = 3.07°C/m; boiling point of pure acetic acid = 117.9°C
A) 117.0°C B) 117.7°C C) 118.1°C D) 118.8°C E) >120°C
118.8˚C
134
Dimethylglyoxime, DMG, is an organic compound used to test for aqueous nickel(II) ions. A solution prepared by dissolving 65.0 g of DMG in 375 g of ethanol boils at 80.3°C. What is the molar mass of DMG?
Kb = 1.22°C/m, boiling point of pure ethanol = 78.5°C
A) 44.1 g/mol
B) 65.8 g/mol
C) 117 g/mol
D) 131.6 g/mol
E) 553 g/mol
117 g/mol
135
Hexachlorophene is used as a disinfectant in germicidal soaps. What mass of hexachlorophene ( = 406.9 g/mol) must be added to 125 g of chloroform to give a solution with a boiling point of 62.60°C? Kb = 3.63°C/m, boiling point of pure chloroform = 61.70°C
A) 12.6 g B) 17.2 g C) 31.0 g D) 34.4 g E) 101 g
12.6 g
136
Cinnamaldehyde ( = 132.15 g/mol) is used as a flavoring agent. What mass of cinnamaldehyde must be added to 175 g of ethanol to give a solution whose boiling point is 82.7°C?
Kb = 1.22°C/m, boiling point of pure ethanol = 78.5°C
A) 62.4 g B) 67.8 g C) 76.2 g D) 78.5 g E) 79.6 g
79.6
137
Calculate the freezing point of a solution made by dissolving 3.50 g of potassium chloride ( = 74.55 g/mol) in 100.0 g of water. Assume ideal behavior for the solution; Kf = 1.86°C/m.
A) –1.7°C B) –0.9°C C) 0.0°C D) 0.9°C E) 1.7°C
-1.7˚C
138
A 0.100 m K2SO4 solution has a freezing point of –0.43°C. What is the van't Hoff factor for this solution? Kf = 1.86°C/m
A) 0.77 B) 1.0 C) 2.3 D) 3.0 E) >3.0
2.3
139
A 0.100 m MgSO4 solution has a freezing point of –0.23°C. What is the van't Hoff factor for this solution? Kf = 1.86°C/m
A) 0.62 B) 1.0 C) 1.2 D) 2.0 E) 4.0
1.2
140
Human blood has a molar concentration of solutes of 0.30 M. What is the osmotic pressure of blood at 25°C?
A) 0.012 atm B) 0.62 atm C) 6.8 atm D) 7.3 atm E) >10. atm
7.3 atm
141
```
Lysine is an amino acid that is an essential part of nutrition but which is not synthesized by the human body. What is the molar mass of lysine if 750.0 mL of a solution containing 8.60 g of lysine has an osmotic pressure of 1.918 atm?
Temperature = 25.0°C
A) 110. g/mol
B) 146 g/mol
C) 220. g/mol
D) 1340 g/mol
E) 1780 g/mol
```
146 g/mol
142
```
Which one of the following pairs of dispersed phases and dispersing media can never form a colloid?
A)
solid and gas
D)
liquid and liquid
B)
liquid and gas
E)
gas and gas
C)
solid and solid
```
gas and gas
143
```
An emulsion is a dispersion consisting of a
A)
solid in a liquid.
D)
liquid in a solid.
B)
liquid in a liquid.
E)
gas in a solid.
C)
gas in a liquid.
```
liquid in liquid
144
```
The Tyndall effect
A)
is observed in concentrated solutions.
B)
is observed only in dilute solutions.
C)
is observed in colloidal dispersions.
D)
is caused by Brownian motion.
E)
is used to determine the osmotic pressure of solutions.
```
is observed in colloidal dispersions.
