Chemistry Chapter 10 Test True/False Indicate whether the sentence or statement is true or false. 1. KMT stands for Kinetic Mole Theory. 2. One of the assumptions in the KMT is that the particles are spread very far apart. 3. Collisions between gas particles and between particles and container walls are elastic collisions. 4. The collisions that gas particles undergo will have a loss of energy according to the KMT. 5. According to the KMT there is an attraction between particles. 6. Gas particles are in constant, random, and rapid motion. 7. Gas particles exhibit the property of expansion. 8. Gas particles have a high density and therefore a low compressibility. 9. The spontaneous mixing of gas particles is called effusion. 10. Ideal gases do not really exist. 11. Particles colliding with walls of a container create pressure. 12. There are 760 torr in 1 atm. 13. There are 101.3 mm Hg in 1 atm. 14. Boyle's law deals with volume and temperature. 15. The combined gas law is composed of volume, pressure, and temperature. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 16. The standard molar volume of a gas at STP is a. 22.4 L. c. g-mol wt/22.4 L.
b. g/22.4 L. d. 1 L. 17. Which of the following equations represents the ideal gas law? a. P = nrtv c. b. d. 18. When pressure, volume, and temperature are known, the ideal gas law can be used to calculate a. the chemical formula. c. molar amount. b. the ideal gas constant. d. compressibility. 19. The value of R, the ideal gas constant, can be calculated from measured values of a gas's pressure, volume, temperature, and a. molar amount. c. rate of diffusion. b. chemical formula. d. density. 20. What is the process by which molecules of a gas randomly encounter and pass through a small opening in a container? a. diffusion c. distillation b. osmosis d. effusion 21. What determines the average kinetic energy of the molecules of any gas? a. temperature c. temperature and pressure b. pressure d. molar mass 22. The equation M A v 2 A = M B v 2 B is an expression of a. Gay-Lussac's law. c. Graham's law. b. Avogadro's law. d. Boyle's law. 23. According to Graham's law, two gases at the same temperature and pressure will have different rates of diffusion because they have different a. volumes. c. kinetic energies. b. molar masses. d. condensation points. 24. Equal volumes of diatomic gases under the same conditions of temperature and pressure contain the same number of a. protons. c. molecules. b. ions. d. Dalton's "ultimate particles." 25. If gas A has a molar mass greater than that of gas B and samples of each gas at identical temperatures and pressures contain equal numbers of molecules, then a. the volumes of gas A and gas B are equal. b. the volume of gas A is greater than that of gas B. c. the volume of gas B is greater than that of gas A. d. their volumes are proportional to their molar masses.
26. What is the volume occupied by 1 mol of water vapor at STP? a. 11.2 L c. 22.4 L b. 18.0 L d. 33.6 L 27. Knowing the mass and volume of a gas at STP allows one to calculate the a. identity of the gas. c. condensation point of the gas. b. molar mass of the gas. d. rate of diffusion of the gas. 28. A 1.00 L sample of a gas has a mass of 1.25 g at STP. What is the mass of 1 mol of this gas? a. a little less then 1.0 g c. 22.4 g b. 1.25 g d. 28.0 g 29. When the ideal gas law reduces to PV = k, the expression is equivalent to a. Avogadro's law. c. Charles's law. b. Avogadro's number. d. Boyle's law. 30. When the ideal gas law reduces to V = kt, the expression is equivalent to a. Boyle's law. c. Avogadro's principle. b. Charles's law. d. Gay-Lussac's law. 31. In a chemical equation, the coefficients for reactants and products that are gases indicate a. volumes at STP. c. molar mass of each substance. b. volume ratios. d. densities. 32. According to Graham's law, the rates of diffusion of two gases at the same temperature and pressure are inversely proportional to a. their volumes. c. their molar masses. b. the square roots of their molar masses. d. their rates of effusion. 33. Suppose that two gases with unequal molar masses were injected into opposite ends of a long tube at the same time and allowed to diffuse toward the center. They should begin to mix a. in approximately five minutes. b. closer to the end that held the heavier gas. c. closer to the end that held the lighter gas. d. exactly in the middle. 34. According to the kinetic-molecular theory, gases condense into liquids because of a. gravity. c. forces between molecules. b. atmospheric pressure. d. elastic collisions. 35. According to the kinetic-molecular theory, which substances are made of particles? a. ideal gases only c. all matter b. all gases d. all matter except solids 36. The kinetic-molecular theory explains the properties of solids, liquids, and gases in terms of the energy of the particles and a. gravitational forces. c. diffusion. b. the forces that act between the particles. d. the mass of the particles.
37. Diffusion between two gases occurs most rapidly if the gases are at a a. high temperature and the molecules are small. b. low temperature and the molecules are large. c. low temperature and the molecules are small. d. high temperature and the molecules are large. 38. Under which conditions do real gases most resemble ideal gases? a. low pressure and low temperature c. high pressure and high temperature b. low pressure and high temperature d. high pressure and low temperature 39. When does a real gas behave like an ideal gas? a. when the particles are far apart b. when the kinetic energy of the particles is low c. when the pressure is high d. when the gas is liquefied 40. What does the constant bombardment of gas molecules against the inside walls of a container produce? a. temperature c. pressure b. density d. diffusion 41. A pressure of 745 mm Hg equals a. 745 torr. c. 1 pascal. b. 1 torr. d. 745 pascal. 42. Convert the pressure 0.75 atm to mm Hg. a. 101.325 mm Hg c. 570 mm Hg b. 430 mm Hg d. 760 mm Hg 43. Standard temperature is exactly a. 100ºC. c. 0ºC. b. 273ºC. d. 0 K. 44. If the temperature of a fixed quantity and volume of gas changes, what also changes? a. pressure c. mass b. density d. formula 45. If the temperature of a fixed quantity of gas decreases and the pressure remains unchanged, a. its volume increases. c. its volume decreases. b. its volume is unchanged. d. its density decreases. 46. Suppose the temperature of the air in a balloon is increased. If the pressure remains constant, what quantity must change? a. volume c. compressibility b. number of molecules d. adhesion 47. Why does the air pressure inside the tires of a car increase when the car is driven? a. Some of the air has leaked out.
b. The air particles collide with the tire after the car is in motion. c. The air particles inside the tire increase their speed because their temperature rises. d. The atmosphere compresses the tire. 48. The volume of a gas is 400.0 ml when the pressure is 1.00 atm. At the same temperature, what is the pressure at which the volume of the gas is 2.0 L? a. 0.5 atm c. 0.20 atm b. 5.0 atm d. 800 atm 49. A sample of oxygen occupies 560. ml when the pressure is 800.00 mm Hg. At constant temperature, what volume does the gas occupy when the pressure decreases to 700.0 mm Hg? a. 80.0 ml c. 600. ml b. 490. ml d. 640. ml 50. At 7.0ºC, the volume of a gas is 49 ml. At the same pressure, its volume is 74 ml at what temperature? a. 3.0ºC c. 120ºC b. 16ºC d. 150ºC 51. A 180.0 ml volume of gas is measured at 87.0ºC. If the pressure remains unchanged, what is the volume of the gas at standard temperature? a. 0.0 ml c. 136 ml b. 0.5 ml d. 410 ml 52. The volume of a sample of oxygen is 300.0 ml when the pressure is 1 atm and the temperature is 27.0ºC. At what temperature is the volume 1.00 L and the pressure 0.500 atm? a. 22.0ºC c. 0.50 K b. 45.0ºC d. 227ºC 53. The volume of a sample of hydrogen is 798 ml and it exerts 621 mm Hg pressure at 5.00ºC. What volume does it occupy at standard temperature and pressure? a. 520. ml c. 745 ml b. 640. ml d. 960 ml 54. To correct for the partial pressure of water vapor, the vapor pressure of H 2 O at the collecting temperature is a. divided by 22.4. c. subtracted from the total gas pressure. b. multiplied by 22.4. d. added to the total gas pressure. 55. Three samples of gas each exert 740. mm Hg in separate 2 L containers. What pressure do they exert if they are all placed in a single 2 L container? a. 247 mm Hg c. 1480 mm Hg b. 740 mm Hg d. 2220 mm Hg Water Vapor Pressure Temperature (ºC) Pressure (mm Hg) 0 4.6 5 6.5 10 9.2 15 12.8
20 17.5 25 23.8 30 31.8 35 42.2 40 55.3 50 92.5 56. What is the partial pressure of water vapor in oxygen gas collected by water displacement at 10ºC and 750 mm Hg? a. 9.2 mm Hg c. 750 mm Hg b. 740.8 mm Hg d. 759.2 mm Hg 57. Calculate the approximate temperature of a 0.50 mol sample of gas at 750 mm Hg and a volume of 12 L. a. 7ºC c. 15ºC b. 11ºC d. 288ºC 58. A sample of gas at 25ºC has a volume of 11 L and exerts a pressure of 660 mm Hg. How many moles of gas are in the sample? a. 0.39 mol c. 9.3 mol b. 3.9 mol d. 87 mol 59. A gas sample with a mass of 0.467 g is collected at 20.ºC and 732.5 mm Hg. The volume is 200. ml. What is the molar mass of the gas? a. 58 g/mol c. 290 g/mol b. 180 g/mol d. 730 g/mol 60. A sample of hydrogen gas diffuses 3.8 times faster than an unknown gas diffuses. What is the molar mass of the unknown gas? a. 3.8 g/mol c. 22.4 g/mol b. 7.6 g/mol d. 28 g/mol Problem 61. Methane, CH 4, and propane, C 3 H 8, are two components of the natural gas burned in Bunsen burners. If a methane molecule travels at 675 m/s from a gas jet, how fast does the propane molecule travel? 62. What is the approximate volume of gas in a 1.50 mol sample that exerts a pressure of 0.922 atm and has a temperature of 10.0 C?
63. A gas sample with a mass of 2.50 g is collected at 20.0 C and 732.5 torr. The volume is 1.28 L. What is the molar mass of the gas? 64. What is the density of argon gas at a pressure of 551 torr and a temperature of 25 degrees Celsius? Essay 65. "When any child of God decides to step out in absolute obedience to the will of God, there will be a frantic effort by the powers of darkness to block him. Obstacles will spring up to hinder that one. The possibility of obedience will seem more and more hopeless. When things are the blackest and most discouraging is the very time not to give up. That kind of namby-pamby surrender will be quickly swamped. To keep looking at our difficulties will also swamp us. We need to look resolutely away from the impossibilities and to the Lord. His help will come, through often it cannot break through to us until the last moment. It is very important that we be ready and prepared for action up to the last split second. God does not even mess that split second. He may seem to be delayed, but he will not be too late for the expectant soul waiting in active faith." In the Arena by Isobel Kuhn Does this quote encourage you or dishearten you? How can you apply this quote to all the busyness that is going on right now? What Scripture passage will help you through this busy time? How is God helping you through this time?