1. 4/24 Bell Work Capt. Frank went to the hardware store to buy something for his home. He asked the clerk, “How much will 1 cost?” The clerk said, “$3.” Frank was puzzled and asked, “How much would 12 cost?” “$6,” replied the clerk,” and 210 would cost $9.”  What is Capt. Frank buying?

2. 4/24 Schedule  Finish Ch 13 Tests – 20 minutes  IA “Observing Volume Changes”  Notes Ch 14.1 “Behavior of Gases” Assignments: 1.

3. Unit: Gas Laws We live at the bottom of a deep gravity well, on the surface of a gas-covered planet going around a nuclear fireball 90 million miles away. -- Douglas Noel Adams in the Salmon of Doubt

4. Ch 14.1 “Properties of Gases” Objectives:  Explain why gases are easier to compress than liquids or solids.  Predict how changing three major variables can effect gases.

5. IA: Observing Volume Changes  Text book p. 412.  Do #1-2, wait 30 minutes, use lamp instead of sunny window.  Be ready to answer the 3 Think about it questions.

6. Properties of Gases In organized soccer, a ball that is properly inflated will rebound faster and travel farther than a ball that is under-inflated. If the pressure is too high, the ball may burst when it is kicked. In this unit, you will study variables that affect the pressure of a gas.

7. Compressibility  Compressibility  Measure of how much volume decreases under pressure.  When a person collides with an inflated airbag, the compression of the gas absorbs the energy of the impact

8. 4/28 Bell Work Harold Bird married a widow. They each had children of their own. 13 years later, the children were fighting. Mrs. Bird exclaimed, “Your children and my children are fighting with our children!”  Each parent is directly related to 9/12 children. How many children were born after the marriage?

9. 4/27 Bell Work Harold Bird married a widow. They each had children of their own. 13 years later, the children were fighting. Mrs. Bird exclaimed, “Your children and my children are fighting with our children!”  Each parent is directly related to 9/12 children. How many children were born after the marriage?

10. 4/27 Schedule  IA “Observing Volume Changes” measurements – QUICKLY!  Finish Ch 14.1 “Behavior of Gases” and start 14.2 “Gas Laws”  SR 14.1 Assignments: 1. SR 14.1 due WEDNESDAY

11. Compressibility Gases are easily compressed.  The distance between particles in a gas is much greater than in a liquid or solid.  Under pressure, the particles in a gas are forced closer together.

12. Compressibility  At room temperature, the distance between particles in an enclosed gas is about 10 times the diameter of a particle.

13. Factors Affecting Gas Pressure  Factors Affecting Gas Pressure  Amount of gas  Volume  Pressure  Temperature

14. Factors Affecting Gas Pressure Four variables generally used to describe a gases are…  pressure (P) in kilopascals  volume (V) in liters  temperature (T) in kelvins  the number of moles (n).

15. Factors Affecting Gas Pressure Amount of Gas  Kinetic theory can predict and explain how gases will respond to a changing conditions. . Increasing the number of particles increases the number of collisions, which is why the gas pressure increases.

16. Factors Affecting Gas Pressure If the gas pressure increases until it exceeds the strength of an enclosed, rigid container, the container will burst.

17. Factors Affecting Gas Pressure  Aerosol Spray Paint

18. Factors Affecting Gas Pressure Volume  You can raise the pressure exerted by reducing its volume.  When the volume of the container is halved, the pressure the gas exerts is doubled.

19. Factors Affecting Gas Pressure Temperature  Increasing temperature increases pressure.  As a gas is heated, the average kinetic energy of the particles increases.  Faster-moving particles strike the walls of their container with more energy.

20. Factors Affecting Gas Pressure When the Kelvin temperature of the enclosed gas doubles, the pressure of the enclosed gas doubles.

21. 14.1 Section Quiz. 1. Compared to liquids and solids, gases are easily compressed because the particles in a gas A.attract each other. B.are spaced relatively far apart. C.are very small. D.repel each other.

22. 14.1 Section Quiz. 2. Gas pressure is affected by A.temperature, volume, and the amount of the gas. B.temperature, volume, and the molar mass of the gas. C.phase diagram, volume, and the size of the container D.temperature, phase diagram, and the mass of the gas container.

23. 14.1 Section Quiz. 3. For gases, the SI units for volume (V), pressure (P), and temperature (T) are, respectively, A.liters, kilopascals, and °C. B.liters, kilopascals, and kelvins. C.cm 3, kilopascals, and kelvins. D.liters, atmospheres, and °C.

24. 4/28 Schedule  Check balloon inquiry activity  Notes Ch 14.2 “The Gas Laws”  Writing Activity Notes: 1.SR 14.1 due TODAY 2.SR 14.2 due TUESDAY

25. The Gas Laws  This hot air balloon was designed to carry a passenger around the world.  You will study some laws that will allow you to predict gas behavior under specific conditions, such as in a hot air balloon.

26. Boyle ’ s Law: Pressure and Volume  As the pressure of a gas increases, the volume decreases.  Assume the temperature is constant

27. Boyle ’ s Law: Pressure and Volume Boyle ’ s law equation

28. Boyle ’ s Law: Pressure and Volume

29. 14.1

31. for Sample Problem 14.1

32. Charles ’ Law: Temperature &Volume Charles ’ Law: Temperature and Volume  As the temperature (in Kelvin) of an enclosed gas increases, the volume increases.  Assume the pressure is constant.

33. Charles ’ s Law: Temperature &Volume As the temperature of the water increases, the volume of the balloon increases.

34. Charles ’ s Law: Temperature &Volume Charles’ law equation

35. Charles ’ s Law: Temperature &Volume

36. 14.2

38. for Sample Problem 14.2

39. Gay-Lussac ’ s Law: Pressure & Temperature Gay-Lussac ’ s Law: Pressure and Temperature  As the temperature (in Kelvin) of an enclosed gas increases, the pressure increases.  Assume the volume is constant.

40. Gay-Lussac ’ s Law: Pressure & Temperature  When a gas is heated at constant volume, the pressure increases.

41. Gay-Lussac ’ s Law: Pressure & Temperature Gay-Lussac ’ s law states that the pressure of a gas is directly proportional to the Kelvin temperature if the volume remains constant.

42. Gay-Lussac ’ s Law: Pressure & Temperature  A pressure cooker demonstrates Gay- Lussac ’ s Law.

43. 14.3

45. Writing Act: Aerosol Can Write a paragraph that answers these questions.  Explain how compressed gas in an aerosol forces the paint out.  Describe how gas pressure changes as paint is sprayed.  ID the variable that causes this change.

46. 4/29 Bell Work A young peasant wanted to marry a princess. The king didn’t approve, but wanted to appear fair. He would put a paper that said MARRIAGE and one that said EXILE. Later the peasant overheard the king was planning to cheat and put in two EXILE slips. Then he made a plan that would guarantee he married the princess.  What did he do?

47. 4/29 Schedule  Finish notes Ch 14.2  Practice on Boyle’s and Charles’ Laws Notes: 1.SR 14.1 LATE 2.SR 14.2 due TODAY

48. for Sample Problem 14.3

49. The Combined Gas Law  Describes the relationship among the pressure, temperature, and volume of an enclosed gas.

50. The Combined Gas Law  This law allows you to do calculations for situations in which only the amount of gas is constant.

51. 14.4

53. for Sample Problem 14.4

54. The Combined Gas Law  Weather balloons carry data- gathering instruments high into Earth ’ s atmosphere. At an altitude of about 27,000 meters, the balloon bursts.

55. 14.2 Section Quiz. 1. If the volume of a gas in a container were reduced to one fifth the original volume at constant temperature, the pressure of the gas in the new volume would be A.one and one fifth times the original pressure. B.one fifth of the original pressure. C.four fifths of the original pressure. D.five times the original pressure.

56. 14.2 Section Quiz. 2. A balloon appears slightly smaller when it is moved from the mountains to the seashore at constant temperature. The best gas law to explain this observation would be A.Gay-Lussacs's Law. B.Graham's Law. C.Boyle's Law. D.Charles's Law.

57. 14.2 Section Quiz. 3. At 46°C and 89 kPa pressure, a gas occupies a volume of 0.600 L. How many liters will it occupy at 0°C and 20.8 kPa? A.0.600 L B.2.58 L C.0.140 L D.2.20 L

58. 4/30 Schedule Seven people meet each other and each shakes hands only once with each of the others.  How many handshakes will there have been?

59. 4/30 Schedule  Notes Ch 14.3 “Ideal Gases”  Work on Boyles’ and Charles’ Law Probs  SR 14.3 Notes: 1.SR 14.1 and SR 14.2 – LATE 2.Boyles’ and Charles’ Law due THURSDAY 3.SR 14.3 due FRIDAY

60. Mixed Gas Laws Problems  Work on the practice problems for Boyle’s Law, Charles’ Law, and the Combined Gas Law.  Explain how to solve these problems to the class. Pick one problem from each type of gas law.  Use doc cam or whiteboard.  Steps to solve  Answer

61. Ch 14.3 “Ideal Gases” Objectives:  Compute the value of an unknown using the ideal gas law.  Compare/contrast real and ideal gases.

62. Ideal Gases  Solid carbon dioxide, or dry ice sublimes.  Dry ice can exist because gases don ’ t obey the assumptions of kinetic theory under all conditions.  You will learn how real gases differ from the ideal gases on which the gas laws are based.

63. Ideal Gas Law  To calculate the number of moles of a contained gas requires an expression that contains the variable n.  What is needed to calculate the amount of gas in a sample at given conditions of volume, temperature, and pressure?

64. Ideal Gas Law  The gas law that includes all four variables—P, V, T, and n.  The ideal gas constant (R) has the value 8.31 (L·kPa)/(K·mol).

65. 14.5

67. for Sample Problem 14.5

68. Ideal Gases and Real Gases  There are attractions between the particles in an ideal gas. Therefore, a gas can condense or solidify, when it is compressed or cooled.  Ideal Gases follow gas laws in ALL conditions.

69. Ideal Gases and Real Gases  Real gases differ most from an ideal gas at low temperatures and high pressures.

70. 14.3 Section Quiz. 1. An aerosol spray can with a volume of 325 mL contains 3.00 g of propane (C 3 H 8 ) as a propellant. What is the pressure in kPa of the gas in the can at 28°C? A.524 kPa B.2.31 10 4 kPa C.475 kPa D.0.524 kPa

71. 14.3 Section Quiz. 2. Find the volume of a gas in liters if 2.95 mol has a pressure of 77.0 kPa at a temperature of 52°C. A.22.4 L B.16.6 L C.103 L D.50.2 L

72. 14.3 Section Quiz. 3. An ideal gas differs from a real gas in that the molecules of an ideal gas A.have no attraction for one another. B.have a significant volume. C.have a molar mass of zero. D.have no kinetic energy.

73. 5/1 Bell Work Duncan Drivel thought it would be nice to join the army, so he went to the local library to find a book on volunteers. While walking along the rows of books, he sees one with VOLIX written on its spine.  How should the title of this book be pronounced?

74. 5/1 Schedule  Grade Sheets  Antacids and Ideal Gas Law Lab  Work on missing assignments Notes: 1.SR 14.1 and SR 14.2 – LATE 2.Boyles’ and Charles’ Law due TODAY 3.SR 14.3 due FRIDAY

75. Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen.  John Steinbeck  Make your own analogy about ideas.  Ideas are like ________________ because ____________. 5/2 Bell Work

76. 5/2 Schedule  Notes Ch 14.4 “Gases: Mixtures and Movements”  Diffusion Lab Notes: 1.SR 14.1 and SR 14.2 – LATE 2.Boyles’ and Charles’ Law LATE 3.SR 14.3 due TODAY Expect Ch 14 “Gases” Test on TUESDAY

77. Gases: Mixtures and Movements A list of gear for an expedition to Mount Everest includes climbing equipment, ski goggles, a down parka with a hood, and most importantly compressed-gas cylinders of oxygen.  You will find out why a supply of oxygen is essential at higher altitudes.

78. Modeling Partial Pressure Write the information in your notebook.  Record the mass of the marbles, blocks, and pennies. Then find the total mass of them all together.  How does the total mass of the objects compare to the sum of the groups?  If you add the paperclips to the mixture, how could you find their mass?

79. Dalton ’ s Law  The total pressure of a mixture of gases is related to the partial pressures of the component gases.

80. Dalton ’ s Law Dalton’s Law of Partial Pressure… Assume constant V and T, the total pressure is equal to the sum of the partial pressures of the component gases.

81. Dalton ’ s Law  Three gases are combined in container T.

82. Dalton ’ s Law The partial pressure of oxygen must be 10.67 kPa or higher to support respiration in humans. The climber below needs an oxygen mask and a cylinder of compressed oxygen to survive.

83. Gas Solubility “Naked Science”Naked Science Can you think of any other examples of Dalton’s Law in humans?  Altitude sickness  Decompression sickness aka “The Bends” Do whales get the bends? Also see Henry’s Law…

84. Diffusion Lab  Make sure to wear goggles and wash hands.  If you have time, do #1 or #2 under the “You’re the Chemist” on p. 437.  Clean-up: Blot Petri dish with paper towel. Wash and return equipment. Wash hands.

85. 5/5 Bell Work You have a cube 5 cm on a side.  Find the volume and surface area.

86. 5/5 Schedule  Finish notes Ch 14.4  Questions Ch 14?  Diffusion Lab “You’re the Chemist” #1-2 p. 437 Notes: 1.SR 14.1, SR 14.2, 14.3 – LATE 2.Boyles’ and Charles’ Law LATE 3.SR 14.4 due TODAY Ch 14 “Gases” Test on TUESDAY

87. 14.6

89. for Sample Problem 14.6

90. Graham ’ s Law Graham ’ s Law: Molar Mass and Rate of Movement  Diffusion is the tendency of molecules to move from areas of high to low concentration.  Effusion, a gas escapes through a tiny hole in its container.  Gases of lower molar mass diffuse and effuse faster than gases of higher molar mass

91. Graham ’ s Law  Bromine vapor is diffusing upward through the air in a graduated cylinder.

92. Graham ’ s Law  After several hours, the bromine has diffused almost to the top of the cylinder.

93. Graham ’ s Law Thomas Graham ’ s Contribution  Graham ’ s law of effusion : the rate of effusion of a gas is inversely proportional to the square root of the gas ’ s molar mass. This law can also be applied to the diffusion of gases.

94. Graham ’ s Law Comparing Effusion Rates  A helium filled balloon will deflate sooner than an air-filled balloon. Why?

95. Graham ’ s Law  The rate of effusion is related only to a particle ’ s speed, so Graham ’ s law can be written as follows for two gases, A and B.

96. Graham ’ s Law Helium effuses (and diffuses) nearly three times faster than nitrogen at the same temperature.

97. 14.4 Section Quiz. 1. What is the partial pressure of oxygen in a diving tank containing oxygen and helium if the total pressure is 800 kPa and the partial pressure of helium is 600 kPa? A.200 kPa B.0.75 kPa C.1.40 10 4 kPa D.1.33 kPa

98. 14.4 Section Quiz. 2. A mixture of three gases exerts a pressure of 448 kPa, and the gases are present in the mole ratio 1 : 2 : 5. What are the individual gas pressures? A.44 kPa, 88 kPa, and 316 kPa B.52 kPa, 104 kPa, and 292 kPa C.56 kPa, 112 kPa, and 280 kPa D.84 kPa, 168 kPa, and 196 kPa

99. 14.4 Section Quiz. 3. Choose the correct words for the spaces. Graham's Law says that the rate of diffusion of a gas is __________ proportional to the square root of its _________ mass. A.directly, atomic B.inversely, atomic C.inversely, molar D.directly, molar

100. Boiling water is poured into a thick-walled drinking glass and a very thin-walled tea cup.  Which is more likely to crack? Why? (Hint: Heat = expansion) 5/6 Bell Work

101. 5/6 Schedule  Questions/specific questions about Ch 14?  Test Ch 14  Work on missing assignments Notes: 1.SR 14.1-14.4 – LATE 2.Boyles’ and Charles’ Law LATE

102. Fingerprint Lab Scenerio : You walk into the chemistry class room to find it a complete mess. Desks, chairs, and equipment are strewn everywhere. Besides denying any involvement in it, Ms. Olson is mysteriously close-lipped about the whole situation. Amidst the mess, you notice a piece of paper that just doesn’t seem to belong in a science classroom… Suspects : see samples

103. Fingerprint Lab Your job…  Work part of a team working to discover “whodunit.”  Collect fingerprint samples from the suspects.  Compare your findings with the the other team to verify your results.

104. 4/25 Schedule  Questions?  Ch 14 “Behavior of Gases”  Notes, Periodic Table, calculator  Quiet until all tests are in  Work on missing assignments Notes: 1.Mixed Gas Laws Problems and SR Ch 14.3 – LATE 2.SR 14.4 and Ch 14 Practice Problems due TODAY

105. 4/25 Bell Work Would you rather be hairbrained or harebrained? Why?

106. 4/28 Bell Work Harold Bird married a widow. They each had children of their own. 13 years later, the children were fighting. Mrs. Bird exclaimed, “Your children and my children are fighting with our children!”  Each parent is directly related to 9/12 children. How many children were born after the marriage?