Boyles Law Problems 1. A gas occupies 12.3 liters at a pressure of 40.0 mm Hg. What is the volume when the pressure is increased to 60.0 mm Hg? 2. If a gas at 25.0 °C occupies 3.60 liters at a pressure of 1.00 atm, what will be its volume at a pressure of 2.50 atm? 3. To what pressure must a gas be compressed in order to get into a 3.00 cubic foot tank the entire weight of a gas that occupies 400.0 cu. ft. at standard pressure? 4. A gas occupies 1.56 L at 1.00 atm. What will be the volume of this gas if the pressure becomes 3.00 atm? 5. A gas occupies 11.2 liters at 0.860 atm. What is the pressure if the volume becomes 15.0 L? 6. 500.0 mL of a gas is collected at 745.0 mm Hg. What will the volume be at standard pressure? 7. Convert 350.0 mL at 740.0 mm of Hg to its new volume at standard pressure. 8. Convert 338 L at 63.0 atm to its new volume at standard pressure. 9. Convert 273.15 mL at 166.0 mm of Hg to its new volume at standard pressure. 10. Convert 77.0 L at 18.0 mm of Hg to its new volume at standard pressure. 11. When the pressure on a gas increases, will the volume increase or decrease? 12. If the pressure on a gas is decreased by one-half, how large will the volume change be? 13. A gas occupies 4.31 liters at a pressure of 0.755 atm. Determine the volume if the pressure is increased to 1.25 atm. 14. 600.0 mL of a gas is at a pressure of 8.00 atm. What is the volume of the gas at 2.00 atm? 15. 400.0 mL of a gas are under a pressure of 800.0 torr. What would the volume of the gas be at a pressure of 1000.0 torr? Gas Law Problems - Boyle's Law Answers: Part One I tried to put the answers in the form of P1V1 = P2V2. They don't have to be in that order, except that the sub ones must be paired on one side of the equals sign and the sub twos must be paired on the other. Some answers at the start are provided. Work the rest out. Show units on all values, not just the answer!! Pay attention to sig figs. 1. (40.0 mm Hg) (12.3 liters) = (60.0 mm Hg) (x); x = 8.20 L, note three significant figures!! 2. (1.00 atm) ( 3.60 liters) = (2.50 atm) (x); x = 1.44 L 3. ( 400.0 cu. ft) (1.00 atm) = (x) (3.00 cubic foot); x = 133 atm 4. (1.56 L) (1.00 atm) = (3.00 atm) (x); 0.520 L 5. (11.2 liters) (0.860 atm) = (x) (15.0 L); x = 0.642 atm 6. ( 745.0 mm Hg) (500.0 mL) = (760.0 mm Hg) (x) 7. (740.0 mm Hg) (350.0 mL) = (760.0 mm Hg) (x) 8. (63.0 atm) (338 L) = (1.00 atm) (x) 9. (166.0 mm Hg) (273.15 mL) = (760.0 mm Hg) (x) 10. (18.0 mm Hg) (77.0 L) = (760.0 mm Hg) (x) 11. Volume will decrease. 12. It will double in size. 13. (0.755 atm) (4.31 liters) = (1.25 atm) (x) 14. (8.00 atm) (600.0 mL) = (2.00 atm) (x) 15. (800.0 torr) (400.0 mL) = (1000.0 torr) (x) Charles Law Problems Abbreviations atm - atmosphere mm Hg - millimeters of mercury (milliliter) torr - another name for mm Hg (liter) = 1000 mL Pa - Pascal (kPa = kilo Pascal) K - Kelvin °C - degrees Celsius 101.325 kPa = 101,325 Pa Conversions K = °C + 273 1 cm3 (cubic centimeter) 1 dm3 (cubic decimeter) Standard Conditions 0.00 °C = 273 K 1.00 atm = 760.0 mm Hg = = 1 mL 1 L = 32. Calculate the decrease in temperature when 2.00 L at 20.0 °C is compressed to 1.00 L. 33. 600.0 mL of air is at 20.0 °C. What is the volume at 60.0 °C? 34. A gas occupies 900.0 mL at a temperature of 27.0 °C. What is the volume at 132.0 °C? 35. What change in volume results if 60.0 mL of gas is cooled from 33.0 °C to 5.00 °C? 36. Given 300.0 mL of a gas at 17.0 °C. What is its volume at 10.0 °C? 37. A gas occupies 1.00 L at standard temperature. What is the volume at 333.0 °C? 38. At 27.00 °C a gas has a volume of 6.00 L. What will the volume be at 150.0 °C? 39. At 225.0 °C a gas has a volume of 400.0 mL. What is the volume of this gas at 127.0 °C? 40. At 210.0 °C a gas has a volume of 8.00 L. What is the volume of this gas at -23.0 °C? 41. The temperature of a 4.00 L sample of gas is changed from 10.0 °C to 20.0 °C. What will the volume of this gas be at the new temperature if the pressure is held constant? 42. Carbon dioxide is usually formed when gasoline is burned. If 30.0 L of CO2 is produced at a temperature of 1.00 x 103 °C and allowed to reach room temperature (25.0 °C) without any pressure changes, what is the new volume of the carbon dioxide? 43. A 600.0 mL sample of nitrogen is warmed from 77.0 °C to 86.0 °C. Find its new volume if the pressure remains constant. 44. What volume change occurs to a 400.0 mL gas sample as the temperature increases from 22.0 °C to 30.0 °C? 45. A gas syringe contains 56.05 milliliters of a gas at 315.1 K. Determine the volume that the gas will occupy if the temperature is increased to 380.5 K 46. A gas syringe contains 42.3 milliliters of a gas at 98.15 °C. Determine the volume that the gas will occupy if the temperature is decreased to -18.50 °C. 47. When the temperature of a gas decreases, does the volume increase or decrease? 48. If the Kelvin temperature of a gas is doubled, the volume of the gas will increase by ____. 49. Solve the Charles' Law equation for V2. 50. Charles' Law deals with what quantities? a. pressure/temperature b. pressure/volume c. volume/temperature d. volume/temperature/pressure 51. If 540.0 mL of nitrogen at 0.00 °C is heated to a temperature of 100.0 °C what will be the new volume of the gas? 52. A balloon has a volume of 2500.0 mL on a day when the temperature is 30.0 °C. If the temperature at night falls to 10.0 °C, what will be the volume of the balloon if the pressure remains constant? Gas Law Problems - Charles' Law Answers: I used V1 / T1 = V2 / T2 to set up the answers. 32. (2.00 L) / 293.0 K) = (1.00 L) / (x); x = 146.5 K 33. (600.0 mL) / (293.0) = (x) / (333.0 K); x = 682 mL 34. (900.0 mL) / (300.0 K) = (x) / (405.0 K); x = 1215 mL 35. (60.0 mL) / (306.0 K) = (x) / (278.00 K) 36. (300.0) / (290.0 K) = (x) / (283.0 K) 37. (1.00 L ) / (273.0 K) = (x) / (606.0 K) 38. (6.00 L) / (300.00 K) = (x) / (423.0 K) 39. (400.0 mL) / (498.0 K) = (x) / (400.0 K) 40. (8.00 L) / (483.0 K) = (x) / (250.0 K) 41. (4.00 L) / (283.0 K) = (x) / (293.0 K) 42. (30.0 L ) / (1273 K) = (x) / (298.0 K) 43. (600.0 mL) / (350.0 K) = (x) / (359.0 K) 44. 400.0 mL / 295.0 K = x / 303.0K 45. 56.05 milliliters / 315.1 K = x / 380.5 K 46. 42.3 milliliters / 371.15 K = x / 254.50 K 47. Decrease. 50. c. volume/temperature 48. Two. Or doubled. 51. 540.0 mL / 273.0 K = x / 373.0 K 49. V2 = (V1 times T2) / T1 52. 2500.0 mL / 303.0 =x / 283.0 K Gas Law Problems- Gay-Lussac's Law Abbreviations atm - atmosphere mm Hg - millimeters of mercury (milliliter) torr - another name for mm Hg (liter) = 1000 mL Pa - Pascal (kPa = kilo Pascal) K - Kelvin °C - degrees Celsius 101.325 kPa = 101,325 Pa Conversions K = °C + 273 1 cm3 (cubic centimeter) 1 dm3 (cubic decimeter) Standard Conditions 0.00 °C = 273 K 1.00 atm = 760.0 mm Hg = = 1 mL 1 L = 56. Determine the pressure change when a constant volume of gas at 1.00 atm is heated from 20.0 °C to 30.0 °C. 57. A gas has a pressure of 0.370 atm at 50.0 °C. What is the pressure at standard temperature? 58. A gas has a pressure of 699.0 mm Hg at 40.0 °C. What is the temperature at standard pressure? 59. If a gas is cooled from 323.0 K to 273.15 K and the volume is kept constant what final pressure would result if the original pressure was 750.0 mm Hg? 60. If a gas in a closed container is pressurized from 15.0 atmospheres to 16.0 atmospheres and its original temperature was 25.0 °C, what would the final temperature of the gas be? 61. A 30.0 L sample of nitrogen inside a rigid, metal container at 20.0 °C is placed inside an oven whose temperature is 50.0 °C. The pressure inside the container at 20.0 °C was at 3.00 atm. What is the pressure of the nitrogen after its temperature is increased? 62. A sample of gas at 3.00 x 103 mm Hg inside a steel tank is cooled from 500.0 °C to 0.00 °C. What is the final pressure of the gas in the steel tank? 63. The temperature of a sample of gas in a steel container at 30.0 kPa is increased from 100.0 °C to 1.00 x 103 °C. What is the final pressure inside the tank? 64. Calculate the final pressure inside a scuba tank after it cools from 1.00 x 103 °C to 25.0 °C. The initial pressure in the tank is 130.0 atm. Gas Law Answers - Gay-Lussac's Law Gay-Lussac's Law is P1 / T1 = P2 / T2 56. 1.00 atm / 293 K = x / 303 K; x = 1.03 atm. 57. 0.370 atm / 323 K = x / 273 K; x = 0.313 atm. 58. 699.0 mm Hg / 313 K = 760 mm Hg / x 59. 750.0 mm Hg / 323.0 K = x / 273.15 K 60. 15.0 atm / 298 K = 16.0 atm / x 61. 3.00 atm. / 293 K = x / 323 62. 3.00 x 103 mm Hg / 773 K = x / 273 63. 30.0 kPa / 173 K = x / 1273 64. 130.0 atm. /1273 K = x / 298 K COMBINED GAS LAW PROBLEMS 73. A gas has a volume of 800.0 mL at minus 23.00 °C and 300.0 torr. What would the volume of the gas be at 227.0 °C and 600.0 torr of pressure? 74. 500.0 liters of a gas are prepared at 700.0 mm Hg and 200.0 °C. The gas is placed into a tank under high pressure. When the tank cools to 20.0 °C, the pressure of the gas is 30.0 atm. What is the volume of the gas? 75. What is the final volume of a 400.0 mL gas sample that is subjected to a temperature change from 22.0 °C to 30.0 °C and a pressure change from 760.0 mm Hg to 360.0 mm Hg? 76. What is the volume of gas at 2.00 atm and 200.0 K if its original volume was 300.0 L at 0.250 atm and 400.0 K. 77. At conditions of 785.0 torr of pressure and 15.0 °C temperature, a gas occupies a volume of 45.5 mL. What will be the volume of the same gas at 745.0 torr and 30.0 °C? 78. A gas occupies a volume of 34.2 mL at a temperature of 15.0 °C and a pressure of 800.0 torr. What will be the volume of this gas at standard conditions? 79. The volume of a gas originally at standard temperature and pressure was recorded as 488.8 mL. What volume would the same gas occupy when subjected to a pressure of 100.0 atm and temperature of minus 245.0 °C? 80. At a pressure of 780.0 mm Hg and 24.2 °C, a certain gas has a volume of 350.0 mL. What will be the volume of this gas under STP 81. A gas sample occupies 3.25 liters at 24.5 °C and 1825 mm Hg. Determine the temperature at which the gas will occupy 4250 mL at 1.50 atm. 82. If 10.0 liters of oxygen at STP are heated to 512 °C, what will be the new volume of gas if the pressure is also increased to 1520.0 mm of mercury? 83. What is the volume at STP of 720.0 mL of a gas collected at 20.0 °C and 3.00 atm pressure? 84. 2.00 liters of hydrogen, originally at 25.0 °C and 750.0 mm of mercury, are heated until a volume of 20.0 liters and a pressure of 3.50 atmospheres is reached. What is the new temperature? 85. A gas balloon has a volume of 106.0 liters when the temperature is 45.0 °C and the pressure is 740.0 mm of mercury. What will its volume be at 20.0 °C and 780 .0 mm of mercury pressure? 86. If the absolute temperature of a given quantity of gas is doubled and the pressure tripled, what happens to the volume of the gas? 87. 73.0 mL of nitrogen at STP is heated to 80.0 °C and the volume increase to 4.53 L. What is the new pressure? 88. 500.0 mL of a gas was collected at 20.0 °C and 720.0 mm Hg. What is its volume at STP? COMBINED GAS LAW ANSWERS 73. x = [ (300 torr) (800 mL) (500 K) ] / [ (250 K) (600 torr) ]; x = 800.0 mL Keep in mind that torr = mmHg. 74. x = [ (700/760) (500) (293) ] / [ (473) (30) ]; x = 9.51 L Note that this problem mixes pressure units. The 700/760 fraction converts mmHg to atm. 75. x = [ (760 mm Hg) (400 mL) (303 K) ] / [ (295 K) (360 mm Hg) ]; x = 867.3 mL 76. x = [ (0.25) (300) (200) ] / [ (400) (2) ] 77. x = [ (785) (45.5) (303) ] / [ (288) (745) ] 78. x = [ (800) (34.2) (273) ] / [ (288) (760) ] 79. x = [ (1) (488.8) (28) ] / [ (273) (100) ] 80. x = [ (780) (350) (273) ] / [ (297.2) (760) ] 81. x = [ (1.50 atm) (4.25 L) (297.5 K) ] / [(1825 mm Hg/760 atm mmHg¯1) (3.25 L) ] Note that we had to change units around somewhat. Also note that a temperature was solved for rather than the usual volume. 82. x = [ (760) (10) (785) ] / [ (273) (1520) ] 83. x = [ (3.00 atm) (720.0 mL) (273 K) ] / [ (293 K) (1.00 atm) 84. x = [ (3.50) (20) (298) ] / [ (750/760) (2.00) ] 85. x = [ (740 mmHg) (106 L) (293 K) ] / [ (318 K) (780 mmHg) ] 86. x = [ (1) (10) (2) ] / [ (1) (3) ] 87. x = [ (1.00 atm) (73.0 mL) (353 K) ] / [ (273 K) (4530 mL) ] 88. x = [ (720) (500) (273) ] / [ (293) (760) ] Gas Law Problems- Dalton's Law 65. A container holds three gases: oxygen, carbon dioxide, and helium. The partial pressures of the three gases are 2.00 atm, 3.00 atm, and 4.00 atm, respectively. What is the total pressure inside the container? 66. A container with two gases, helium and argon, is 30.0% by volume helium. Calculate the partial pressure of helium and argon if the total pressure inside the container is 4.00 atm. 67. If 60.0 L of nitrogen is collected over water at 40.0 °C when the atmospheric pressure is 760.0 mm Hg, what is the partial pressure of the nitrogen? 68. 80.0 liters of oxygen is collected over water at 50.0 °C. The atmospheric pressure in the room is 96.00 kPa. What is the partial pressure of the oxygen? 69. A tank contains 480.0 grams of oxygen and 80.00 grams of helium at a total pressure of 7.00 atmospheres. Calculate the following. a) How many moles of O2 are in the tank? b) How many moles of He are in the tank? c) Total moles of gas in tank. d) Mole fraction of O2. e) Mole fraction of He. f) Partial pressure of O2. g) Partial pressure of He. 70. A tank contains 5.00 moles of O2, 3.00 moles of neon, 6.00 moles of H2S, and 4.00 moles of argon at a total pressure of 1620.0 mm Hg. Complete the following table Moles O2 Ne H2S Ar Total 18.00 Mole fraction 1 Partial pressure 1620 Vapor Pressure Data for H2O If you need to convert to atmospheres, divide by 101.325. If you need to convert to millimeters of mercury, divide by 101.325, then multiply by 760.0 Temperature 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 kPa 0.61129 0.65716 0.70605 0.75813 0.81359 0.8726 0.93537 1.0021 1.073 1.1482 1.2281 1.3129 1.4027 1.4979 1.5988 1.7056 1.8185 1.938 2.0644 2.1978 2.3388 2.4877 2.6447 2.8104 2.985 3.169 3.3629 3.567 3.7818 4.0078 4.2455 4.4953 4.7578 5.0335 5.3229 5.6267 5.9453 6.2795 6.6398 6.9969 7.3814 7.784 8.2054 8.6463 9.1075 9.5895 10.094 10.62 11.171 11.745 Temperature 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 kPa 12.344 12.97 13.623 14.303 15.012 15.752 16.522 17.324 18.159 19.028 19.932 20.873 21.851 22.868 23.925 25.022 26.163 27.347 28.576 29.852 31.176 32.549 33.972 35.448 36.978 38.563 40.205 41.905 43.665 45.487 47.373 49.324 51.342 53.428 55.585 57.815 60.119 62.499 64.958 67.496 70.117 72.823 75.614 78.494 81.465 84.529 87.688 90.945 94.301 97.759