Chapter 11-12 CHEM102
Calculate the amount of heat required to raise the temperature of 165 g of water from 12.0°C to 88.0°C. (Sp. heat of H2O = 4.18 J/g•°C) a. 52.4 kJ b. 1.93 J c. 60.7 kJ d. 1.46 kJ e. 15.6 J
A. 52.4 kJ
Which liquid would have the highest viscosity at room temperature? a. C8H17NH2 b. C7H14 c. C9H18 d. C5H12 e. CH3NH2
A. C8H17NH2
Which of the following boils at the lowest temperature? a. CF4 b. HF c. HCl d. KI e. SiF4
A. CF4
Which one of the following would have the highest molar heat of vaporization? a. CH3NH2 b. CH4 c. C2H6 d. SiH4 e. H2S
A. CH3NH2
For which of the following would hydrogen bonding not be an important factor in determining physical properties in the liquid state? a. HBr b. H2O c. HF d. NH3 e. H2O2
A. HBr
Which technique listed below separates a mixture of liquids on the basis of their boiling points? a. distillation b. extraction c. filtration d. reflux e. none of these
A. distillation
Identify which property liquids do not have in common with solids. a. rigid shape b. volumes do not change significantly with pressure c. hydrogen bonding forces can be significant d. practically incompressible e. volumes do not change significantly with temperature
A. rigid shape
The most stable situation for liquid surface molecules is one in which the surface area is minimal. For a given volume, what shape has the least possible surface area? a. spherical b. cubic c. elliptical d. parabolic e. none of these
A. spherical
Car wax works to repel water because ____. a. wax exerts a very low adhesive force for water. b. the cohesive forces in water are very low. c. of capillary action present. d. the water adheres well with the wax. e. none of these.
A. wax exerts a very low adhesive force for water.
Which statement is false? a. In the absence of a phase change, the viscosity of a liquid increases as temperature decreases. b. All other factors being equal, if adhesive forces are strong, capillary action is likely to occur less readily than if adhesive forces are weak. c. The shape of a meniscus depends on the difference between the strengths of cohesive forces and adhesive forces. d. Coating glass with a nonpolar polymer greatly reduces the adhesion of the water to the glass. e. Capillary action helps plant roots take up water.
B. All other factors being equal, if adhesive forces are strong, capillary action is likely to occur less readily than if adhesive forces are weak.
Which response includes all of the following compounds that exhibit hydrogen bonding and no other compounds? CH4, AsH3, CH3NH2, H2Te, HF a. AsH3, H2Te b. CH3NH2, HF c. CH4, AsH3, H2Te d. AsH3, CH3NH2 e. HF, H2Te
B. CH3NH2, HF
For which of the following would permanent dipole-dipole interactions play an important role in determining physical properties in the liquid state? a. BF3 b. ClF c. BeCl2 d. F2 e. CCl4
B. ClF
Which of these liquids would have the highest surface tension at 25°C? a. Br2 b. H2O c. CCl4 d. C5H12 e. CH3OCH3
B. H2O
Which one of the following boils at the lowest temperature? a. H2O b. H2S c. H2Se d. H2Te e. H2Po
B. H2S
Dispersion forces are the only significant factor affecting boiling point for all the following compounds except? a. Ar b. H2SO4 c. CF4 d. Br2 e. CH4
B. H2SO4
Which of the following interactions are the strongest? a. hydrogen bonding force b. ion-ion interactions c. permanent dipole force d. dispersion force e. London force
B. ion-ion interactions
Which one of the following statements does not describe the general properties of liquids accurately? a. In the liquid state the close spacing of molecules leads to large intermolecular forces that are strongly dependent on the nature of the molecules involved. b. Liquids are practically incompressible. c. As the temperature of a liquid is increased, the vapor pressure of the liquid decreases. d. The normal boiling point of a liquid is the temperature at which the vapor pressure of the liquid becomes equal to exactly 760 torr. e. Vapor pressures of liquids at a given temperature differ greatly, and these differences in vapor pressure are due to the nature of the molecules in different liquids.
C. As the temperature of a liquid is increased, the vapor pressure of the liquid decreases.
Which of the following substances will have the strongest intermolecular forces? a. H2S b. NO c. CH3NH2 d. HCl e. Rn
C. CH3NH2
For which of the following would dispersion forces be the most important factor in determining physical properties in the liquid state? a. H2O b. NaCl c. F2 d. HF e. NH4Cl
C. F2
Which one of the following boils at the lowest temperature? a. KNO3 b. XeF4 c. Kr d. NH3 e. AsH3
C. Kr
Which one of the following statements does NOT describe the general properties of liquids accurately? a. Liquids have characteristic volumes that do not change greatly with changes in temperature. (Assuming that the liquid is not vaporized.) b. Liquids have characteristic volumes that do not change greatly with changes in pressure. c. Liquids diffuse only very slowly when compared to solids. d. The liquid state is highly disordered compared to the solid state. e. Liquids have high densities compared to gases.
C. Liquids diffuse only very slowly when compared to solids.
Volatile liquids are described by all of the following except: a. Volatile liquids are easily vaporized. b. Volatile liquids have relatively high vapor pressures. c. Volatile liquids have strong cohesive forces. d. Volatile liquids have weak intermolecular forces. e. All of these describe volatile liquids.
C. Volatile liquids have strong cohesive forces.
Which of the following interactions are the strongest? a. hydrogen bonding b. London forces c. covalent bonds d. ion-ion interactions e. dispersion forces
C. covalent bonds
Which property is not affected by strength of intermolecular forces? a. viscosity b. boiling point c. density d. vapor pressure e. molar heat of vaporization
C. density
As we increase the temperature of a liquid, its properties change. Which of the following would not be an expected change in the properties of a typical liquid as we increase its temperature? a. decrease in viscosity b. decrease in density c. increase in surface tension d. increase in vapor pressure e. increase in tendency to evaporate
C. increase in surface tension
On a relative basis, the weaker the intermolecular forces in a substance are, a. the larger is its heat of vaporization. b. the more it deviates from the ideal gas law. c. the greater is its vapor pressure at a particular temperature. d. the larger is its molar heat capacity as a liquid. e. the higher is its boiling point.
C. the greater is its vapor pressure at a particular temperature.
The term used to describe resistance to flow of a liquid is ____. a. surface tension b. capillary action c. viscosity d. vapor pressure e. vaporization
C. viscosity
The ΔHvap is related to the strength of intermolecular forces. Which of the following has the lowest ΔHvap? a. C3H8 b. C6H12 c. C3H7OH d. C3H7NH2 e. C8H18
C3H8
How much heat is released when 165 g of liquid benzene, C6H6 , cools from 78.0°C to 12.0°C? (Sp. heat of C6H6 = 1.74 J/g•°C) a. 4.35 J b. 6.26 kJ c. 45.5 kJ d. 18.9 kJ e. 22.4 kJ
D. 18.9 kJ
All of the following are gases at room temperature and atmospheric pressure. Which one will liquefy most easily when pressurized at a certain temperature? a. H2 b. Ar c. SiH4 d. NH3 e. F2
D. NH3
Which of the following does not correctly describe viscosity? a. Viscosity is the resistance to flow of a liquid. b. Viscosity can be measured with a viscometer. c. The greater the ability of a liquid to hydrogen bond, the higher the viscosity. d. The smaller the molecule, the higher the viscosity. e. All of these correctly describe viscosity.
D. The smaller the molecule, the higher the viscosity.
The boiling points of the halogens increase in the order F2 < Cl2 < Br2 < I2 due to the resulting increasing ____ interactions. a. ion-dipole b. hydrogen-bonding c. ion-ion d. dispersion forces e. permanent dipole-dipole
D. dispersion forces
Which response correctly identifies all the interactions that might affect the properties of BrI? a. dispersion force, ion-ion interaction b. hydrogen bonding force, dispersion force c. permanent dipole force d. permanent dipole force, dispersion force e. dispersion force
D. permanent dipole force, dispersion force
Which of the following boils at the highest temperature? a. C2H6 b. C3H8 c. C4H10 d. C5H12 e. C6H14
E. C6H14
Which one of the following statements does not describe the general properties of solids accurately? a. Solids have characteristic volumes that do not change greatly with changes in temperature. b. Solids have characteristic volumes that do not change greatly with changes in pressure. c. Solids diffuse only very slowly when compared to liquids and gases. d. Solids are not fluid. e. Most solids have high vapor pressures at room temperature.
E. Most solids have high vapor pressures at room temperature.
Which response correctly identifies all the interactions that might affect the properties of BF3? a. dispersion force, ion-ion interaction b. hydrogen bonding force, dispersion force c. permanent dipole force d. permanent dipole force, dispersion force e. dispersion force
E. dispersion force
Capillary action is ____ a. resistance to flow. b. the rate of collisions for gas molecules. c. the energy required to overcome the attractive forces between molecule in the liquid state to form a gas. d. the force required to expand the surface of a liquid. e. the drawing of a liquid up the inside of a small-bore tube when adhesive forces exceed cohesive forces.
E. the drawing of a liquid up the inside of a small-bore tube when adhesive forces exceed cohesive forces.
At what temperature and pressure do the three phases coexist in equilibrium? a. 0.127atm and 63.1K b. 0.127atm and 63.2K c. 1.00atm and 77.4K d. 1.00atm and 63.2K e. 33.5atm and 126.0K
a. 0.127atm and 63.1K
Calculate the amount of energy required to melt a 48.9g sample of cobalt at its normal melting point. Boiling point = 3097oC Δ Hvap = 389 kJ/mol melting point = 1495oC Δ Hfus = 15.5 kJ/mol specific heat solid = 0.418 J/goC specific heat liquid = 0.686 J/goC a. 12.9 kJ b. 18.7 kJ c. 20.5 kJ d. 323 kJ e. 759 kJ
a. 12.9 kJ
What is the specific heat of a metal if a ten gram sample at 40.2°C is dropped into 100 grams of water at 25.4°C and the temperature rises to 28.6°C? (Sp. heat of H2O = 4.18 J/g•°C) a. 2.11 J/g °C b. 0.085 J/g °C c. 206 J/g °C d. 1.92 J/g °C e. 20.9 J/g °C
a. 2.11 J/g °C
The conduction band of magnesium is thought to result from the combination of molecular orbitals resulting from overlap of ____ atomic orbitals. a. 3s and 3p b. 3s and 3d c. 3d and 4s d. 3p and 3d e. 3s and 4s
a. 3s and 3p
If 100. grams of liquid water at 100.°C and 200. grams of water at 20.0°C are mixed in an insulated container, what will the final temperature of the mixture be? (Sp. heat of H2O = 4.18 J/g•°C) a. 46.7°C b. 60.0°C c. 66.7°C d. 73.3°C e. 77.8°C
a. 46.7°C
Calculate the amount of heat absorbed by 10.0 grams of ice at −15.0°C in converting it to liquid water at 50.0°C. (Sp. heat of H2O(s) = 2.09 J/g•°C, Sp. heat of H2O = 4.18 J/g•°C, heat of fusion of H2O(s) = 333 J/g) a. 5.73 × 103 J b. 6.76 × 102 J c. 1.70 × 102 J d. 2.83 × 103 J e. 3.29 × 103 J
a. 5.73 × 103 J
The metal potassium crystallizes in a body-centered cubic lattice. If the radius of potassium is 227 pm, what is the unit cell edge length? a. 524 pm b. 454 pm c. 303 pm d. 227 pm e. 98.3 pm
a. 524 pm
Strontium crystallizes in a face-centered cubic lattice. The radius of strontium is 214 pm. What is the edge length of the unit cell? a. 605 pm b. 428 pm c. 856 pm d. 454 pm e. 214 pm
a. 605 pm
What is the simplest formula of the compound represented by the unit cell provided below? a. AB2 b. AB3 c. AB d. A2B4 e. A2B6
a. AB2
Which of the following solid compounds has the highest melting point? a. Al2O3 b. MgF2 c. NaF d. CaF2 e. AlF3
a. Al2O3
Which of the following compounds would be expected to have the highest melting point? a. BaF2 b. BaCl2 c. BaBr2 d. BaI2 e. NaF
a. BaF2
An unknown white solid was found to have a melting point of 150oC. It is soluble in water, but it is a poor conductor in aqueous solution. Which of the following substances is the most likely? a. C6H12O6 (glucose) b. KCl c. Rb d. C (diamond) e. Si
a. C6H12O6 (glucose)
Which one of the following melts at the lowest temperature at a given pressure? a. CH4 b. SiH4 c. NH3 d. SOCl2 e. H2O
a. CH4
Which of the following compounds has a boiling point closest to that of argon? a. F2 b. Cl2 c. HCl d. NaF e. HF
a. F2
Which of the following compounds would have the highest boiling point? a. KCl b. CH3OCH3 c. CH3CH2CH3 d. CH3CH2NH2 e. C12H22O11
a. KCl
Which of the above would you predict to have the highest surface tension? a. N-ethylpropanamide c. ethyl methyl ketone b. diethyl ether d. cyclopentane
a. N-ethylpropanamide
What is the densest phase for nitrogen? a. Solid b. Liquid c. Gas d. supercritical fluid
a. Solid
Which of the following statements concerning the accompanying phase diagram is false? a. The solid is less dense than the liquid. b. Point C is the critical point of the substance. c. Point A is the triple point of the substance. d. The normal boiling point is below the triple point. e. The curve AD divides the solid region from the gas region.
a. The solid is less dense than the liquid.
Which picture below depicts the physical state present at 70K and 1.00atm? a. all across the bottom b. stacked in the center c. spread out
a. all across the bottom
Which of the following in the solid state would be an example of a molecular crystal? a. carbon dioxide b. graphite c. cesium fluoride d. iron e. quartz
a. carbon dioxide
For crystal structures that contain only one kind of atom, the nearest neighbors of each atom can be visualized as lying along a line of the unit cell. For a simple cubic structure what is the orientation of that line with respect to the unit cell and how many atomic radii does it contain? a. cell edge and 2 atomic radii b. face diagonal and 4 atomic radii c. body diagonal and 3 atomic radii d. face diagonal and 2 atomic radii e. body diagonal and 4 atomic radii
a. cell edge and 2 atomic radii
Identify the line segment on the diagram below where the specific heat of the solid is used to calculate energy flow: a. line segment A - B b. line segment B - D c. line segment D - F d. line segment F - H e. line segment H - J
a. line segment A - B
The space-filling representation provided below is an example of a _____ unit cell, which contains _____ atom(s). a. simple cubic, 1 atom b. body centered cubic, 2 atoms c. face centered cubic, 4 atoms d. simple cubic, 8 atoms e. body centered cubic, 3 atoms
a. simple cubic, 1 atom
The densest phase of F2 is a a. solid b. liquid c. gas
a. solid
Strontium crystallizes in a face-centered cubic lattice. The density of the element is 2.63 g/cm3. What is the volume of a single unit cell? a.2.21 x 10^-22 cm3 b. 1.53 x 10^-21 cm3 c.2.88 x 10^-26 cm3 d.5.53 x 10^-23 cm3 e.3.83 x 10^-22 cm3
a.2.21 x 10^-22 cm3
The density of palladium is 12.0 g/cm3. The unit cell of Pd is a face-centered cube. Calculate the atomic radius of Pd. a. 1.26Å b. 1.37Å c. 1.44Å d. 1.56Å e. 1.64Å
b. 1.37Å
How much heat would be required to convert 234.3 g of solid benzene, C6H6(s), at 5.5°C into benzene vapor, C6H6(g), at 100.0°C? mp of C6H6(s) = 5.5°C bp of C6H6 = 80.1°C molar heat of fusion at 5.5°C = 9.92 kJ/mol molar heat of vaporization at 80.1°C = 30.8 kJ/mol molar heat capacity of C6H6 = 136 J/mol•°C molar heat capacity of C6H6(g) = 81.6 J/mol•°C a. 106 kJ b. 158 kJ c. 53 kJ d. 32 kJ e. 5049 kJ
b. 158 kJ
At 10.0oC, the vapor pressure of nitric acid is 26.6 mmHg, and at 50.0oC, the vapor pressure is 208 mmHg. Using this information, calculate the heat of vaporization (ΔHvap) of nitric acid. a. 25.6 kJ/mol b. 39.1 kJ/mol c. 48.4 kJ/mol d. 225 kJ/mol e. 566 kJ/mol
b. 39.1
Metallic calcium crystallized in a face-centered cubic lattice and the atomic radius of calcium is 1.97Å. Calculate the edge length, a, of a unit cell of calcium. a. 4.19Å b. 5.57Å c. 6.05Å d. 6.24Å e. 6.83Å
b. 5.57Å
What is the normal melting point for nitrogen? a. 63.1K b. 63.2K c. 77.4K d. 126.0K
b. 63.2K
A chemical reaction releases 58,500 J of heat into 150 g of water. Assuming no heat is lost to the surroundings, what is the temperature increase of the water? (Sp. heat of H2O = 4.18 J/g•°C) a. 36.1°C b. 93.2°C c. 20.2°C d. 106.4°C e. 0.03°C
b. 93.2°C
As iron is heated to 1181K, it adopts one type of cubic cell (A); then, as the temperature rises to 1674K, it changes to another cubic cell (B). The iron is changing from a _______ unit cell to a _______unit cell. a. Body-centered cubic → simple cubic b. Body-centered cubic → face-centered cubic c. Face-centered cubic → simple cubic d. Face-centered cubic → body-centered cubic e. Simple cubic → face-centered cubic
b. Body-centered cubic → face-centered cubic
Which liquid would evaporate most quickly at room temperature? a. H2O, 18 g/mol b. Gasoline, C8H18, 114 g/mol c. Vegetable oil, 895 g/mol d. Mineral oil, C12H26, 170 g/mol e. Ethylene glycol, HO−CH2−CH2−OH, 62 g/mol
b. Gasoline, C8H18, 114 g/mol
Substances have properties that are related to their structures. Which of the following statements regarding properties of solids is not expected to be correct? a. Solid potassium should be a good conductor of electricity. b. Solid CaSO4 should sublime readily. c. Molten LiCl should be a good conductor of electricity. d. Graphite should have a high melting point. e. Solid CO2 should have a low melting point.
b. Solid CaSO4 should sublime readily.
Which of the following statements is false? a. Solids exhibit vapor pressures, just as liquids do. b. Solids with low vapor pressures sublime easily. c. Dry ice vaporizes at atmospheric pressure and room temperature without passing through the liquid state. d. Deposition occurs when a vapor solidifies without passing through the liquid state. e. Most solids have much lower vapor pressures than liquids do.
b. Solids with low vapor pressures sublime easily.
Which one of the following statements is not applicable to metallic solids? a. The units that occupy the lattice points are positive ions. b. The binding forces in metallic solids are shared electron pairs. c. The melting points of metallic solids vary over a large range. d. The hardness of metallic solids varies from quite soft to quite hard. e. Metallic solids conduct electric current well.
b. The binding forces in metallic solids are shared electron pairs.
Amorphous solids are characterized by all the following statements except: a. Amorphous solids have no well-defined, ordered structure. b. The intermolecular forces between their particles are constant throughout the solid. c. Some amorphous solids are able to flow, like liquids. d. Amorphous solids do not exhibit sharp melting points. e. Amorphous solids shatter irregularly.
b. The intermolecular forces between their particles are constant throughout the solid.
Which one of the following pairs is incorrectly matched? Substance / Classification a. sand / covalent solid b. diamond / molecular solid c. Fe / metallic solid d. CaF2 / ionic solid e. quartz / covalent solid
b. diamond / molecular solid
The melting point of a solid is the same as the ____ of its liquid. a. boiling point b. freezing point c. sublimation point d. triple point e. critical point
b. freezing point
Which one of the following is not a general property of ionic solids? a. hard and brittle b. good electrical conductors in the solid state c. relatively high melting points d. strongest interparticle attractions are electrostatic e. positions of ions define the unit cell (lattice)
b. good electrical conductors in the solid state
Identify the line segment on the above diagram where the enthalpy of fusion is used to calculate energy flow: a. line segment A - B b. line segment B - D c. line segment D - F d. line segment F - H e. line segment H - J
b. line segment B - D
At 0.50 atm and 60K, F2 is a: a. solid b. liquid c. gas
b. liquid
Changes in pressure have ____ effects on melting point; changes in pressure have ____ effects on boiling points. a. small; small b. small; large c. large; small d. large; large e. unknown; unknown
b. small; large
Some solids can be converted directly to the vapor phase by heating. The process is called ____. a. fusion b. sublimation c. vaporization d. condensation e. distillation
b. sublimation
The amount of energy associated with holding the individual particles (atoms, ions, or molecules) together in a crystal lattice is most directly related to ____. a. the specific heat of the solid b. the heat of fusion of the solid c. the specific heat of the liquid d. the density of the solid e. the heat of condensation of the liquid
b. the heat of fusion of the solid
In a body-centered cubic lattice, how many atoms are contained in a unit cell? a. one b. two c. three d. four e. five
b. two
In a face-centered cubic lattice, an atom laying in a face of a unit cell is shared equally by how many unit cells? a. one b. two c. eight d. four e. sixteen
b. two
In the metallic bonding of Na, the conduction band consists of ____ molecular orbitals and the empty band consists of ____ molecular orbitals. a. σ2s and σ*2s b. σ3s and σ*3s c. σ*2s and σ2s d. σ*3s and σ*3s e. σ*3s and σ3s
b. σ3s and σ*3s
Which of the following, in the solid state, would be an example of a molecular crystal? a. diamond b. copper c. phosphorus trichloride d. magnesium fluoride e. sodium chloride
c. phosphorus trichloride
Metallic calcium crystallized in a face-centered cubic lattice, and the atomic radius of calcium is 1.97Å. Calculate the density of calcium. a. 1.28 g/cm3 b. 1.42 g/cm3 c. 1.54 g/cm3 d. 1.84 g/cm3 e. 2.11 g/cm3
c. 1.54 g/cm3
Using the Clausius-Clapeyron equation determine the vapor pressure of water at 50.0°C. The molar heat of vaporization of water is 40.7 kJ/mol. a. 700 torr b. 450 torr c. 100 torr d. 80 torr e. 55 torr
c. 100 torr
The vapor pressure of liquid iron is 400mmHg at 2890K. Assuming that its heat of vaporization is 356 kJ/mol, calculate the vapor pressure of liquid iron at a temperature of 3110K. a. 400.4 mmHg b. 360.2 mmHg c. 1140.8 mmHg d. 444.2 mmHg e. 140.2 mmHg
c. 1140.8 mmHg
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. 2.26 × 105 J b. 3.05 × 104 J c. 2.40 × 105 J d. 2.20 × 104 J e. 6.43 × 105 J
c. 2.40 × 105 J
Calculate the amount of heat required to convert 10.0 grams of ice at −20.°C to steam at 120.°C. (Sp. heat of H2O(s) = 2.09 J/g•°C, Sp. heat of H2O = 4.18 J/g•°C, Sp heat of H2O(g) = 2.03 J/g•°C; heat of fus. of H2O(s) = 333 J/g, heat of vap. of H2O = 2260 J/g) a. 18.6 kJ b. 26.3 kJ c. 30.9 kJ d. 41.2 kJ e. 46.4 kJ
c. 30.9 kJ
What is the normal boiling point temperature of F2? a. 53.4 K b. 53.5 K c. 85.0 K d. 144.1 K
c. 85.0 K
What type of compound is depicted above? (C = dark atoms, H = light atoms) a. Binary acid b. Binary ionic c. Covalent - molecular d. Covalent - network e. Ternary ionic
c. Covalent - molecular
Which one of the following statements is not applicable to covalent solids? a. The units that occupy the lattice points are atoms. b. The binding forces in covalent solids are shared electrons. c. Covalent solids have low melting points. d. Covalent solids are very hard. e. Covalent solids do not conduct electric current well.
c. Covalent solids have low melting points.
What is the strongest type of interparticle force present in the solid H2S? a. Ion-ion c. Dipole-dipole b. Hydrogen-bonding d. Dispersion
c. Dipole-dipole
Arrange the following in order of increasing melting points. CsCl, BaCl2, diamond (C), H2, HF a. H2 < HF < BaCl2 < CsCl < diamond b. HF < H2 < CsCl < BaCl2 < diamond c. H2 < HF < CsCl < BaCl2 < diamond d. H2 < HF < diamond < CsCl < BaCl2 e. HF < H2 < diamond < CsCl < BaCl2
c. H2 < HF < CsCl < BaCl2 < diamond
Which one of the following crystallizes in a metallic lattice? a. C10H8 b. graphite c. In d. As e. KMnO4
c. In
Which statement about crystal structure is false? a. Polymorphous substances have more than one crystal structure. b. Rhombic, triclinic and cubic are examples of crystal structures. c. In a cubic lattice, four other cells share an atom lying at the corner of the unit cell equally. d. Isomorphous substances have only one crystal structure. e. Amorphous substances have no organized crystal structure.
c. In a cubic lattice, four other cells share an atom lying at the corner of the unit cell equally.
Both solid and liquid CCl4 are molecular in nature. Which of the following statements is true? a. Liquid CCl4 is much more compressible and more highly ordered than solid CCl4. b. The liquid CCl4 molecules are attracted to one another by covalent bonds. c. Liquid CCl4 is a slightly disordered arrangement of molecules with somewhat restricted mobility. d. Liquid CCl4 is a state in which there is little effect contributed by intermolecular forces on the physical properties of CCl4. (The liquid CCl4 does not feel the effects of intermolecular forces).
c. Liquid CCl4 is a slightly disordered arrangement of molecules with somewhat restricted mobility.
Which one of the following elements is considered an insulator? a. Fe b. Ga c. N d. Ge e. Si
c. N
Which of the following statements is correct? a. KCl will have a higher vapor pressure at 25oC than HF b. NH3 will have a higher boiling point than BeO c. NH3 will have a lower vapor pressure at -50oC than NO d. N2 will have a higher boiling point than NO e. CH3CH2CH3 will have a lower vapor pressure at -50oC than CH3OCH3
c. NH3 will have a lower vapor pressure at -50oC than NO
An unknown substance was found to have a melting point of ~300oC and was not soluble water. It is a good conductor in both the melt and solid states. Which of the following substances is the most likely? a. C6H12O6 (glucose) b. KCl c. Rb d. C (diamond) e. Si
c. Rb
Which one of the following is an ionic solid? a. graphite b. nickel c. ammonium chloride d. silicon carbide, SiC e. sucrose, C12H22O11
c. ammonium chloride
The electrical conductivity of a metal ____ with increasing temperature and that of a semiconductor ____ with increasing temperature. a. increases; increases b. increases; decreases c. decreases; increases d. decreases; decreases e. remains the same; increases or decreases
c. decreases; increases
In any cubic lattice, an atom at the corner of a unit cell is shared equally by how many unit cells? a. one b. two c. eight d. four e. sixteen
c. eight
Shown below is the unit cell for sodium chloride. The larger spheres represent the chloride anions. How would you describe the crystal packing structure for the chloride anions? a. simple cubic b. body-centered cubic c. face-centered cubic
c. face-centered cubic
In a face-centered cubic lattice, how many atoms are contained in a unit cell? a. one b. two c. four d. five e. six
c. four
Which of the following is an amorphous solid? a. graphite b. sodium chloride c. glass d. quartz e. diamond
c. glass
Identify the line segment on the above diagram where the specific heat of the liquid is used to calculate energy flow: a. line segment A - B b. line segment B - D c. line segment D - F d. line segment F - H e. line segment H - J
c. line segment D - F
Which type of solid is expected for Ga? a. covalent b. ionic c. metallic d. molecular e. intensive
c. metallic
Which one of the following is a metallic solid? a. graphite b. sulfur c. sodium d. silicon e. neon
c. sodium
How much heat is absorbed if 45 grams of sweat is evaporated from someone's skin? ΔHvap for water at body temperature is 2.41 kJ/g. a. 43,400 J b. 53.6 kJ c. 108.5 J d. 108,500 J e. 115,100 J
d. 108,500 J
How much heat is released when 40.0 g of steam at 250.0°C cools and condenses to water at 30.0°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. 24.0 kJ b. 23.0 J c. 32.9 kJ d. 114 kJ e. 122 kJ
d. 114 kJ
How much energy is given off when 55.0g of steam at 115.0oC is cooled to water at 75.0oC? (csteam = 2.0 J/goC cwater = 4.18 J/goC cice = 2.03 J/goC) (ΔHvap = 40.7 kJ/mol ΔHfus = 6.02 kJ/mol) a. 7.52 kJ b. 25.8 kJ c. 116.8 kJ d. 131.6 kJ e. 4400 kJ
d. 131.6 kJ
What is the heat of fusion of chromium (in kJ/mol) if 10.0 grams of solid chromium absorb 2.82 × 103 J of heat in melting at 2173 K, its melting point? a. 1.34 b. 6.86 c. 48.5 d. 14.7 e. 34.3
d. 14.7
What would be the final temperature of the system if 30.0 g of lead at 150.°C is dropped into 10.0 g of water at 10.0°C in an insulated container? (Sp. heat of H2O = 4.18 J/g•°C, Sp. heat of Pb(s) = 0.128 J/g•°C) a. 12.4°C b. 16.8°C c. 19.4°C d. 21.7°C e. 24.6°C
d. 21.7°C
The metal niobium crystallizes in a body-centered cubic unit cell. When x-rays with a wavelength of 0.8302Å are used, the second-order (n=2) Bragg reflection from a set of parallel planes in a niobium crystal is observed at an angle of θ = 14.57ο. If the distance between these planes corresponds to a unit cell length (d = a), calculate the edge length of the niobium unit cell. a. 0.209Å b. 0.915Å c. 1.65Å d. 3.30Å e. 1005Å
d. 3.30Å
What is the normal boiling point of methanol? a. 50oC b. 55oC c. 60oC d. 65oC e. 70oC
d. 65oC
What is the coordination number for each sphere (metal ion) in a body-centered cubic structure? a. 4 b. 3 c. 6 d. 8 e. 12
d. 8
You have a white, crystalline solid which has a melting point of 800oC. It does not conduct electricity in the solid phase, but it forms a conducting solution when dissolved in water. Which of the following is the most likely formula for this compound? a. Mg b. Si c. CCl4 d. AlCl3 e. C6H12O6
d. AlCl3
Which statement is false? a. The size of an ion in a crystal is influenced by its environment, that is, by the other ions surrounding it. b. About 26% of the total volume of any cubic close packed crystal lattice is empty space. c. Two solids that crystallize in the same kind of crystal lattice are said to be isomorphous. d. An example of an amorphous solid is graphite. e. Elements and compounds can have more than one crystal structure.
d. An example of an amorphous solid is graphite.
Which one of the following is classified as a covalent solid? a. K2SO4 b. Cu c. Co d. C e. CH4
d. C
Which one of the following is a molecular solid? a. NH4Cl b. K c. SiC d. C6H6 e. KC2H3O2
d. C6H6
Which one of the following pairs is incorrectly matched? Substance / Classification a. H2O / molecular solid b. paraffin / molecular solid c. KF / ionic solid d. CsI / covalent solid e. Ni / metallic solid
d. CsI / covalent solid
Arrange the following in order of increasing melting points. KCl, He, H2O, HF a. He < H2O < HF < KCl b. H2O < HF < He < KCl c. KCl < H2O < HF < He d. He < HF < H2O < KCl e. H2O < He < KCl < HF
d. He < HF < H2O < KCl
Which of the compounds above has the strongest intermolecular forces? a. Carbon disulfide, CS2 b. Methanol, CH3OH c. Ethanol, CH3CH2OH d. Heptane, CH3CH2CH2CH2CH2CH2CH3 e. Cannot tell from the information provided
d. Heptane, CH3CH2CH2CH2CH2CH2CH3
Choose the statement which best explains why the boiling point of ICl (97 oC) is higher than the boiling point of Br2 (59 oC): a. The molecular weight of ICl is 162.4, while that of Br2 is 159.8. b. London dispersion forces are much stronger for ICl than for Br2. c. ICl is an ionic compound, while Br2 is a molecular compound. d. ICl is polar, while Br2 is nonpolar. e. There is hydrogen bonding in ICl, but not in Br2.
d. ICl is polar, while Br2 is nonpolar.
Which one of the following statements is not applicable to ionic solids? a. The units that occupy the lattice points are ions. b. The binding forces in ionic solids are electrostatic attractions. c. Most ionic solids are hard and brittle. d. Ionic solids are usually excellent conductors of electric current. e. Ionic solids have fairly high melting points.
d. Ionic solids are usually excellent conductors of electric current.
Which one of the following statements is not applicable to molecular solids? a. The units that occupy the lattice points are molecules. b. The binding forces in molecular solids are dispersion forces or dispersion forces and dipole-dipole interactions. c. Molecular solids have relatively low melting points. d. Molecular solids are usually excellent conductors of electric current. e. Molecular solids are soft compared to covalent solids.
d. Molecular solids are usually excellent conductors of electric current.
A certain compound is formed by directional covalent bonds with a large gap between the filled and empty molecular orbitals. It has a melting point of 1800oC. What is the crystal structure? a. Ionic b. Metallic c. Molecular d. Network
d. Network
An unknown metal crystallized in the hexagonal closest-packed structure and has a density of 12.2 g/cm3. Its atomic radius is 1.34Å. There are 4 atoms per unit cell. What is the metal? a. Mg b. Ba c. Fe d. Ru e. Au
d. Ru
Substances have properties that are related to their structures. Which of the following statements regarding properties of solids is not expected to be correct? a. Molten KBr should be a good conductor of electricity. b. Diamond should have a high melting point. c. Solid sodium should be a good conductor of electricity. d. Solid CaF2 should have a low melting point. e. Silicon carbide, SiC, should not sublime readily.
d. Solid CaF2 should have a low melting point.
Which of the following does not affect the amount of heat transferred in solids? a. The value of specific heat. b. The amount of mass. c. The nature of the solid. d. The rate the temperature change occurred. e. The size of the temperature change.
d. The rate the temperature change occurred.
Which of the above would you predict to have the highest vapor pressure? a. N-ethylpropanamide c. ethyl methyl ketone b. diethyl ether d. cyclopentane
d. cyclopentane
In a cubic lattice, an atom on the edge of a unit cell is shared equally by how many unit cells? a. one b. two c. eight d. four e. twelve
d. four
Elements that have their highest energy electrons in a filled band of molecular orbitals that is separated from the lowest empty band by an energy difference much too large for electrons to jump between bands are called ____. a. semiconductors b. metals c. conductors d. insulators e. isomorphs
d. insulators
Identify the line segment on the diagram below where the enthalpy of vaporization is used to calculate energy flow: a. line segment A - B b. line segment B - D c. line segment D - F d. line segment F - H e. line segment H - J
d. line segment F - H
Which type of solid is expected for SO2? a. covalent b. ionic c. metallic d. molecular e. hypersaturated
d. molecular
Consider the metallic bonding in lithium. The interaction of all the 2s orbitals of one mole of lithium atoms produces a band consisting of ____ mole(s) of molecular orbitals (σ2s and σ∗2s). a. one-eighth b. one-fourth c. one-half d. one e. two
d. one
Which one of the following substances is incorrectly matched with the kind of solid it forms? Substance / Kind of Solid a. sulfur dioxide / molecular b. graphite / covalent c. calcium bromide / ionic d. potassium / ionic e. methane / molecular
d. potassium / ionic
Which one of the following is a covalent solid? a. sulfur trioxide b. nickel c. ammonium chloride d. silicon carbide, SiC e. sucrose, C12H22O11
d. silicon carbide, SiC
The metal lead crystallizes in a face-centered cubic lattice with an edge length of 495.1 pm. What is the density of lead? a. 0.709 g/cm3 b. 2.84 g/cm3 c. 1.42 g/cm3 d. 5.67 g/cm3 e. 11.3 g/cm3
e. 11.3 g/cm3
In ideal close-packed structures of metallic solids, how many nearest neighbors does a metal ion have? a. 4 b. 3 c. 6 d. 8 e. 12
e. 12
When X-rays with λ = 193.7 pm are used, the second-order Bragg reflection from a set of parallel planes in a rubidium crystal occurs at an angle θ = 29.37°. Calculate the distance between the planes in the crystal. a. 6.595 pm b. 62.00 pm c. 124.0 pm d. 197.5 pm e. 394.9 pm
e. 394.9 pm
What will be the final temperature of the liquid water resulting from the mixing of 10.0 grams of steam at 130.°C with 40.0 g of ice at −10.0°C? (Sp. heat of H2O(s) = 2.09 J/g•°C, Sp. heat of H2O = 4.18 J/g•°C, Sp. heat of H2O(g) = 2.03 J/g•°C; heat of fusion of H2O(s) = 333 J/g, heat of vap. of H2O = 2260 J/g) a. 80.4°C b. 72.6°C c. 54.3°C d. 46.1°C e. 63.3°C
e. 63.3°C
If 10.0 g of ice at −10.0°C is placed in 200. g of water at 80.0°C in an insulated container, what will be the temperature of the system when equilibrium is established? (Sp. heat of H2O(s) = 2.09 J/g•°C, Sp. heat of H2O = 4.18 J/g•°C, heat of fus. of H2O(s) = 333 J/g) a. 76°C b. 65°C c. 27°C d. 20°C e. 72°C
e. 72°C
f 10.0 g of steam at 110.0°C is pumped into an insulated vessel containing 100. g of water at 20.0°C, what will be the equilibrium temperature of the mixture? (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. 86.8°C b. 54.5°C c. 58.4°C d. 38.6°C e. 76.9°C
e. 76.9°C
How much heat is released at constant pressure if a 18.0-L tank containing 42.0 atm of hydrogen sulfide gas condenses at its boiling point of -60.0oC? The enthalpy of vaporization of hydrogen sulfide is 18.7 kJ/mol at -60.0oC. (R = 0.0821 L • atm/(K • mol)) a. 1.22 × 102 J b. 2.87 × 106 J c. 4.33 × 102 J d. 1.87 × 104 J e. 8.08 × 105 J
e. 8.08 × 105 J
A sketch of the phase diagram (not to scale) of water is given below. Which statement concerning the path (broken line) is false? a. At point E the water is all solid (ice). b. If heat is added to the ice at point E, the temperature of the ice increases until line AB is reached, then the temperature remains constant until all of the ice is melted into liquid. c. Once all the ice has melted (at the intersection of the broken line and line AB) the temperature of the water increases as heat is added until point F is reached. d. If more heat is added upon reaching point F, the temperature will remain constant as the liquid water vaporizes. e. Another way to vaporize all of the liquid water at point F is to increase the pressure.
e. Another way to vaporize all of the liquid water at point F is to increase the pressure.
Which response has the following substances arranged in order of increasing boiling point? Ar, NaClO3, H2O, H2Se a. NaClO3 < H2O < H2Se < Ar b. NaClO3 < H2Se < H2O < Ar c. Ar < NaClO3 < H2Se < H2O d. Ar < H2O < H2Se < NaClO3 e. Ar < H2Se < H2O < NaClO3
e. Ar < H2Se < H2O < NaClO3
You have a white, crystalline solid which melts at 88oC. It does not conduct electricity in the solid phase, and when it dissolves in water it still does not conduct electricity. Which of the following is the most likely formula for this compound? a. Mg b. Si c. CCl4 d. AlCl3 e. C6H12O6
e. C6H12O6
Which substance would be expected to have the highest heat of vaporization? a. Cl2 b. CCl4 c. C2Cl4 d. CH3OCH3 e. CH2OHCH2OH
e. CH2OHCH2OH
A sketch of a phase diagram is given below. Which statement about this diagram is not true? a. Increasing pressure at constant temperature can melt the solid. b. Increasing temperature at constant pressure can cause the solid to sublime. c. Increasing temperature at constant pressure can cause the liquid to vaporize. d. Increasing pressure at constant temperature can cause deposition of solid from gas. e. Increasing pressure at constant temperature can cause liquid to freeze.
e. Increasing pressure at constant temperature can cause liquid to freeze.
Krypton (Kr) is able to be liquefied at low temperatures due to which intermolecular force? a. ionic bonding b. covalent bonding c. hydrogen bonding d. dipole-dipole e. London dispersion
e. London dispersion
Arrange the following ionic compounds in order of increasing melting points. NaF, MgF2, AlF3, NaBr, NaI a. NaF < NaBr < NaI < MgF2 < AlF3 b. NaBr < NaI < NaF < AlF3 < MgF2 c. MgF2 < AlF3 < NaF < NaI < NaBr d. AlF3 < MgF2 < NaF < NaBr < NaI e. NaI < NaBr < NaF < MgF2 < AlF3
e. NaI < NaBr < NaF < MgF2 < AlF3
Which one of the following elements is considered a semiconductor? a. Li b. Fe c. Cl d. Ni e. Si
e. Si
Which of the following solids could be described in this way: high melting point, hard solid, poor electrical conductor, non-electrolytic solution. a. NH3 b. Mg c. H2S d. MgCl2 e. SiO2
e. SiO2
Which statement is false? a. Molecular solids generally have lower melting points than covalent solids. b. Metallic solids exhibit a wide range of melting points. c. The lattice of a metallic solid is defined by the position of the metal nuclei, and the valence electrons are distributed over the lattice as a whole. d. Most molecular solids melt at lower temperatures than metallic solids. e. The interactions among the molecules in molecular solids are generally stronger than those among the particles that define either covalent or ionic lattices.
e. The interactions among the molecules in molecular solids are generally stronger than those among the particles that define either covalent or ionic lattices.
A sketch of the phase diagram (not to scale) of water is given below. Which statement is false? a. Line AD is the sublimation curve − solid and vapor are in equilibrium. b. Point A is the triple point − solid, liquid, and vapor are at equilibrium. c. Line AC is the vapor pressure curve − liquid and gas (vapor) are in equilibrium. d. Line AB is the melting curve − solid and liquid are in equilibrium. e. The slope of line AB is negative showing that as the liquid is cooled, the molecules get closer and closer together as they solidify.
e. The slope of line AB is negative showing that as the liquid is cooled, the molecules get closer and closer together as they solidify.
For crystal structures that contain only one kind of atom, the nearest neighbors of each atom can be visualized as lying along a line of the unit cell. For a body-centered cubic structure what is the orientation of that line with respect to the unit cell and how many atomic radii does it contain? a. cell edge and 2 atomic radii b. face diagonal and 4 atomic radii c. body diagonal and 3 atomic radii d. face diagonal and 2 atomic radii e. body diagonal and 4 atomic radii
e. body diagonal and 4 atomic radii
Identify the line segment on the above diagram where the specific heat of the gas is used to calculate energy flow: a. line segment A - B b. line segment B - D c. line segment D - F d. line segment F - H e. line segment H - J
e. line segment H - J
Which of the following involves a change in temperature during the phase transition? a. deposition of carbon dioxide b. fusion of ethanol c. condensation of ammonia d. all of the above e. none of the above
e. none of the above
A single substance that can crystallize in more than one arrangement is said to be ____. a. isomorphous b. amorphous c. primitive d. triclinic e. polymorphous
e. polymorphous
The electron sea model explains ______. a. the chemical reactivity of most metals b. why most metals are solids at room temperature c. the thermal conductivity of metals by the easy flow of nuclei d. the electrical conductivity of metals by the easy flow of nuclei e. the electrical conductivity of metals by the easy flow of electrons
e. the electrical conductivity of metals by the easy flow of electrons