Gases, Liquids, and Solids Exam Prep Chapter.7 4th Edition

General, Organic and Biological Chemistry, 4e (Smith)

Chapter 7 Gases, Liquids, and Solids

1) Which assumption is NOT part of the kinetic-molecular theory of gases?

A) A gas consists of particles that move randomly and rapidly.

B) The size of gas particles is small compared to the space between the particles.

C) Because the space between gas particles is large, gas particles exert no attractive forces on each other.

D) The kinetic energy of gas particles does not change with increasing temperature.

E) When gas particles collide with each other, they rebound and travel in new directions.

2) A patient's systolic pressure is measured as 128 mm Hg. What is this pressure in units of atm?

A) 128 atm

B) 1.28 atm

C) 0.168 atm

D) 9.73 x 104 atm

E) 8.71 atm

3) An aerosol can has a pressure of 1.86 atm. What is this pressure expressed in units of mm Hg?

A) 1.86 mm Hg

B) 1410 mm Hg

C) 1860 mm Hg

D) 0.00245 mm Hg

4) A scuba diver typically begins a dive with a compressed air tank at 2,350 psi. What is this pressure expressed in units of mm Hg?

A) 160. mm Hg

B) 3.09 mm Hg

C) 1.21 × 105 mm Hg

D) 1.79 × 106 mm Hg

E) 45.5 mm Hg

5) A scuba diver typically begins a dive with a compressed air tank at 2,350 psi. What is this pressure expressed in units of atmospheres?

A) 160. atm

B) 2.35 atm

C) 3.45 × 104 atm

D) 3.09 atm

E) 45.5 atm

6) A scuba diver typically begins a dive with a compressed air tank at 2,350 psi. What is this pressure expressed in units of Pa?

A) 0.0232 Pa

B) 3.09 Pa

C) 2.38 × 108 Pa

D) 1.62 × 107 Pa

E) 45.5 Pa

7) A birthday balloon contains helium at a pressure of 815 torr. What is this pressure expressed in units of mm Hg?

A) 815 mm Hg

B) 1.07 mm Hg

C) 0.815 mm Hg

D) 6.19 × 105 mm Hg

8) A sample of neon gas has a volume of 5.0 mL at a pressure of 1.50 atm. What is the pressure exerted by the gas if the volume is increased to 30.0 mL, at constant temperature?

A) 0.25 atm

B) 9.0 atm

C) 1.5 atm

D) 0.21 atm

E) 7.5 atm

9) Which gas law describes the relationship between the volume and temperature of a sample of gas at constant pressure?

A) Boyle's law

B) Charles's law

C) Gay-Lussac's law

D) Avogadro's law

E) Dalton's law

10) A balloon that contains 0.500 L of helium at 25 °C is cooled to 11 °C, at a constant pressure. What volume does the balloon now occupy?

A) 0.22 L

B) 1.1 L

C) 0.477 L

D) 0.525 L

E) 0.500 L

11) A 54.2 L sample of gas at 115 K is heated to 345 K, at constant pressure. What volume does the gas now occupy?

A) 2.15 × 106 L

B) 163 L

C) 18.1 L

D) 732 L

12) The temperature of a 0.750-L gas sample at 25 °C and 2.00 atm is changed to 250 °C. What is the final pressure of the system, at constant volume?

A) 20.0 atm

B) 0.200 atm

C) 3.51 atm

D) 0.427 atm

13) A weather balloon contains 233 L of helium at 22 °C and 760. mm Hg. What is the volume of the balloon when it ascends to an altitude where the temperature is –54 °C and 511 mm Hg?

A) 2.24 × 107 L

B) 467 L

C) 116 L

D) 257 L

14) A gas cylinder containing 6.38 mol of neon has a pressure of 491 mm Hg at 295 K. If 3.22 mol of helium is added to this cylinder, at constant temperature and volume, what will be the pressure in the cylinder?

A) 9.73 mm Hg

B) 739 mm Hg

C) 1460 mm Hg

D) 248 mm Hg

15) How many moles are contained in 5.33 L of O2 at standard temperature and pressure?

A) 5.33 mol of O2

B) 1.00 mol of O2

C) 0.238 mol of O2

D) 22.4 mol of O2

E) 4.20 mol of O2

16) Which cylinder at STP will contain the greatest number of gas particles?

A) a 5.0-L cylinder of neon

B) a 5.0-L cylinder of helium

C) a 5.0-L cylinder of nitrogen

D) a 5.0-L cylinder of hydrogen

E) All of the cylinders contain the same number of gas particles.

17) Which cylinder at STP will contain the greatest mass of gas particles?

A) a 5.0-L cylinder of neon

B) a 5.0-L cylinder of helium

C) a 5.0-L cylinder of nitrogen

D) a 5.0-L cylinder of hydrogen

E) All of the cylinders contain the same mass of gas particles.

18) Consider the balanced reaction: Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g). What volume of H2(g) at STP can be generated when 134 g of zinc reacts?

A) 2.05 L

B) 45.9 L

C) 5.98 L

D) 3.00 × 103 L

19) How many moles of gas are contained in a scuba diver's 12.6-L tank filled with 3422 psi of air at 25 °C?

A) 1760 moles

B) 2.10 × 104 moles

C) 120. moles

D) 1430 moles

20) A sample of gas contains four gases with the following partial pressures: He (113 mm Hg), Ne (184 mm Hg), Ar (35 mm Hg), and Xe (445 mm Hg). What is the total pressure of the sample?

A) 777 mm Hg

B) 760. mm Hg

C) 445 mm Hg

D) 332 mm Hg

21) A sample of gas contains four gases (He, Ne, Ar, and Xe) with the following partial pressures: He (43 mm Hg), Ar (835 mm Hg), and Xe (111 mm Hg). If the total pressure in the container is 1355 mm Hg, what is the partial pressure of Ne in the sample?

A) 989 mm Hg

B) 760. mm Hg

C) 366 mm Hg

D) 323 mm Hg

22) Propanol, CH3CH2CH2OH, has the structure shown below. What is the strongest type of intermolecular force that exists between two propanol molecules?

A) London dispersion forces

B) Hydrogen bonding

C) Temporary dipole interactions

D) Dipole-dipole interactions

23) Butane, CH3CH2CH2CH3, has the structure shown below. What is the strongest type of intermolecular force that exists between two butane molecules?

A) London dispersion forces

B) Hydrogen bonding

C) Temporary dipole interactions

D) Dipole-dipole interactions

24) Which compound has the lowest boiling point?

A)

B)

C)

D)

25) Which of the following compounds has the highest boiling point?

A)

B)

C)

D)

26) Surface tension measures which of the following?

A) A liquid's resistance to flow

B) A liquid's resistance to spreading out

C) A liquid's ability to boil at low temperatures

D) The molecular weight of a compound

27) Which is a molecular solid?

A) MgCl2

B) Au

C) Glass

D) Graphite

E) Sucrose (C12H22O11)

28) Which is an ionic solid?

A) KCl

B) Cu

C) SiO2

D) Rubber

E) Polyethylene

29) Which is a network solid?

A) NaBr

B) Ag

C) SiO2

D) Na

E) Sucrose (C12H22O11)

30) The normal boiling point of a liquid is the temperature at which its vapor pressure equals which of the following?

A) 1 mm Hg

B) 760 mm Hg

C) The pressure above the liquid

D) The vapor pressure of water

31) Consider the two liquids A and B shown in closed containers. Which liquid has the higher vapor pressure?

A) Liquid A

B) Liquid B

C) Both Liquids A and B have equal vapor pressures.

D) Not enough information is given.

32) Consider the two liquids A and B shown in closed containers. Which liquid exhibits the stronger intermolecular forces?

A) Liquid A

B) Liquid B

C) Both Liquids A and B have equal vapor pressures.

D) Not enough information is given.

33) Which molecule(s) exhibit hydrogen bonding?

A) CH4

B) CHCl3

C) NF3

D) HF

E) All of the molecules exhibit hydrogen bonding.

34) Which molecule(s) exhibit London dispersion forces?

A) Kl

B) CH4

C) NH3

D) HBr

E) All of the molecules exhibit London dispersion forces.

35) Which molecule(s) exhibit hydrogen bonding?

A) H2S

B) CH4

C) NH3

D) HCl

E) All of the molecules exhibit London dispersion forces.

36) Which molecule has the lowest surface tension?

A)

B)

C)

D)

37) Three of the four phase changes below are endothermic. Which phase change is NOT endothermic?

A) Vaporization

B) Sublimation

C) Condensation

D) Melting

38) Which phase change below is endothermic?

A) Deposition

B) Melting

C) Condensation

D) Freezing

39) What is the volume of 62.3 g of nitrogen gas at STP?

A) 22.4 L

B) 49.8 L

C) 99.6 L

D) 2.78 L

40) What volume does 7.50 × 1020 molecules of O2 occupy at STP?

A) 22.4 L

B) 1.68 × 1022 L

C) 0.0279 L

D) 2.79 L

41) Air pressure at the bottom of Death Valley, at 282 ft below sea level, is 776 mm Hg. What are the partial pressures of O2 and N2, which compose 21% and 78% of the atmosphere, respectively?

A) 210 mm Hg O2 and 780 mm Hg N2

B) 160 mm Hg O2 and 610 mm Hg N2

C) 160 mm Hg O2 and 590 mm Hg N2

D) 163 mm Hg O2 and 613 mm Hg N2

42) Which gas sample contains the largest number of moles?

A) 4.0 L of O2 at 273 K and 530 mm Hg

B) 4.5 L of N2 at 298 K and 610 mm Hg

C) 3.8 L of He at 250 K and 880 mm Hg

D) 5.0 L Ar at 300 K and 710 mm Hg

43) Atmospheric pressure in interstellar space is approximately 1 × 10–17 torr at a temperature of –173 °C. How many gas molecules are present in 25,000 L of interstellar space (about the volume of a bedroom)?

A) 2 × 107 molecules

B) 4 × 10–17 molecules

C) 2 × 1010 molecules

D) 3 × 10–14 molecules

44) An aerosol spray can with a volume of 350 mL registers a pressure of 4.5 atm at room temperature. What happens to the pressure of the gas inside the can if the can is stored outside during the winter months?

A) The pressure of the gas will remain at 4.5 atm.

B) The pressure of the gas will be greater than 4.5 atm.

C) The pressure of the gas will be less than 4.5 atm.

D) It is impossible to predict without knowing the amount of gas present inside the can.

45) At rest, the volume of air in the lungs is 615 mL at 760 mm Hg. When the volume of the lungs expands during inhalation, what happens to the pressure inside the lungs?

A) The pressure inside the lungs decreases, which draws air into the lungs.

B) The pressure inside the lungs increases, which forces air inside the lungs.

C) The pressure inside the lungs remains constant, and air readily flows into the lungs.

D) The pressure inside the lungs cannot be determined if the weight of the person is unknown.

46) When octane evaporates, what kind of attractive forces are overcome?

A) Covalent bonding between carbon and hydrogen atoms

B) Hydrogen bonding between octane molecules

C) Dipole-dipole interactions between octane molecules

D) London dispersion forces between octane molecules

47) Hydrogen peroxide decomposes to give water and oxygen gas according to the equation below. If 3.0 moles of hydrogen peroxide decompose, what volume of oxygen gas is produced at a pressure of 1.0 atm and a temperature of 23 °C?

2 H2O2(l) → 2 H2O(l) + O2(g)

A) 1.9 L of O2

B) 2.8 L of O2

C) 24 L of O2

D) 36 L of O2

E) 73 L of O2

48) Whether a substance exists as a gas, liquid, or solid depends on the balance between the kinetic energy of its particles and the strength of the interactions between the particles.

49) The size of gas particles is large compared to the space between the particles.

50) When a sample of gas is compressed from 6.0 L to 2.0 L at a constant temperature, the pressure of the gas triples.

51) When a sample of gas is heated from 80 °C to 160 °C at a constant pressure, the volume of the gas doubles.

52) London dispersion forces are the strongest type of intermolecular forces.

53) STP is defined as a pressure of exactly one atmosphere and a temperature of 25 °C.

54) If 10.0 g of Ne and 10.0 g of N2 are put into a 5.0 L container, the partial pressure of N2 will be less than the partial pressure of Ne in the container.

55) London dispersion forces are exhibited by all covalent compounds.

56) The stronger the intermolecular forces, the lower the vapor pressure of a substance at a given temperature.

57) When the pressure and temperature are held constant, the volume of a gas is inversely proportional to the number of moles present.

58) If the lungs of a child hold 0.11 mol of air in a volume of 2.8 L, then the lungs of an average female adult, with a volume is 4.6 L, can be expected to hold 0.18 mol of air.

59) A gas cylinder containing 3.88 mol of helium has a pressure of 549 mm Hg at 298 K. If 1.22 mol of neon is added to this cylinder, at constant temperature and volume, the pressure will rise to 1750 mm Hg.

60) The value of the universal gas constant, R, changes as a function of temperature.

61) The numerical value of the universal gas constant, R, depends on its units.

62) Two molecules of dimethyl ether, whose structure is shown below, are capable of hydrogen bonding with each other.

63) Evaporation is an endothermic process.

64) Viscosity is a measure of the resistance of a liquid to flow freely.

65) Ethylene glycol is expected to be less viscous than propane.

66) All solids are crystalline solids.

67) When the volume of a sample of gas is doubled and the Kelvin temperature is cut in half, the pressure of a sample remains constant.

68) When the volume of a sample of gas is doubled and the Kelvin temperature is doubled, the pressure of a sample remains constant.

69) The density of a sample of gas increases if the temperature is increased but the pressure is held constant.

70) A 22.4 g sample of O2 will occupy less than 22.4 L at STP.

71) It requires less heat to melt a 10-g sample of water than to vaporize a 10-g sample of water.

72) Polypropylene, a typical plastic, is an example of an amorphous solid.

73) If two compounds have the same molecular formula they will have the same boiling point.

74) The higher the vapor pressure of a compound, the higher the boiling point of the compound.

75) NaCl has a higher melting point than sucrose (C12H22O11).

76) Energy is released when a less organized state is converted to a more organized state.

77) Gas pressure is the result of particles of gas colliding with each other.

78) Gases expand to fill the volume and shape of their container because the rapidly moving particles experience negligible attractive forces for each other.

79) The pressure of a gas is proportional to its Kelvin temperature at constant volume and number of moles. Therefore increasing the temperature increases the pressure.

80) Freeze-drying removes water from foods by the process of sublimation.

81) London dispersion forces are also referred to as van der Waals forces.

82) When 88.4 g of hydrogen gas is put in a 25.8-L container at 300. K, the pressure will be 83.7 atm.

83) Charles's law can be used to explain the dangerous condition for scuba divers called "the bends," which is caused by the formation of nitrogen gas bubbles in the bloodstream.

84) Condensation is the opposite of sublimation.

85) Sarin, a nerve gas once used as a chemical weapon, has a melting point of –56 °C and a boiling point of 158 °C. A sample of sarin at room temperature (22 °C) exists as a liquid.

86) The energy required to break up the attractions between ethylene glycol molecules is greater than the energy required to break up the attractions between propane molecules.

87) Some nail polish removers contain acetone. When acetone evaporates, the covalent bonds between the carbon, hydrogen, and oxygen atoms are broken.

88) The kinetic energy of gas particles ________ with increasing temperature.

89) Gay–Lussac's law relates the ________ and temperature of a gas sample at constant volume.

90) The type(s) of intermolecular forces exhibited by hydrogen bromide molecules, HBr, is/are ________.

91) The type(s) of intermolecular forces exhibited by methane molecules, CH4, is/are ________.

92) Graphite is an example of a ________ solid.

93) _____ is the pressure exerted by gas molecules in equilibrium with the liquid phase.

94) Given these vapor pressures at 20 °C: butane, 1,650 mm Hg; acetaldehyde, 740 mm Hg, Freon-113, 284 mm Hg, the compound with the lowest boiling point is ________.

95) _____ are due to momentary changes in electron density in a molecule.

96) The physical change indicated below represents the ________ of ethanol (C2H5OH).

C2H5OH(g) → C2H5OH(l)

97) If 225 cal of heat is added to 15.0 g of 2-propanol at room temperature, 25ºC, the ethanol will reach a final temperature of ________ ºC. The specific heat of 2-propanol is 0.612 cal/(g•ºC).

98) One would need to add ________ calories of heat to increase the temperature of 100.0 g of ethanol from 20ºC to 27ºC? The specific heat of ethanol is 0.583 cal/(g•ºC).