1. Energy and States of Matter

2. Energy When particles collide, energy is transferred from one particle to another. Law of conservation of energy: energy can be neither created nor destroyed; it can only be converted from one form to the other.

3. Particle Diagram Draw particle diagrams of water molecules for solid, liquid, and gas. http://www.fda.gov/Food/ResourcesForYou /Consumers/ucm197586.htm http://www.volusia.org/services/ public-works/water-resources- and-utilities/ http://teacouncil.net/make-the-perfect-cup- of-tea/ Solid/Ice Liquid/Water Gas/Steam

4. Particle Diagram

5. http://www.patana.ac.th/secondary/science/anrophysics/unit5/co mmentary.htm SolidLiquid Gas Motion/Kinetic Energy of Particles Force of Attraction for the Same Substance

6. PhET Simulation

7. Solids Physical properties used to describe solids: Hardness Shape Malleable Ductile Density Elasticity Characteristics of solids: Particles are very close together Strong attractive forces between particles Particles vibrate but do not move out of position Fixed shape Fixed volume

8. Liquids Physical properties used to describe liquids: Viscosity (resistance to flow) Concentration Fluid (has the ability to flow) Density Characteristics of liquids: ▫ Particles are close together ▫ Weak attractive forces between particles ▫ Particles slide past each other ▫ Takes the shape of the container ▫ Fixed volume ▫ compressible ▫ Cohesion (ex. water-water) ▫ Adhesion (ex. Water-leaf surface)

9. Gasses Properties ▫ Particles are far apart ▫ No attractive forces between particles ▫ Takes the shape of the container ▫ Particles spread out to fill the container ▫ Can be identified by “burning splint” test:  O 2 gas causes the burning splint to re-light  CO 2 gas causes the burning splint to go out quietly (fire extinguisher)  H 2 gas causes a popping sound

10. Real-world application Why are “air bags” safer than “liquid bags” or “solid bags”? http://www.superstock.com/stock-photos-images/1570R-134389

11. Gasses as Diatomic Molecules  There are seven elements (all gasses) whose atoms are not stable as individuals.  These atoms will always bond with another atom.  If no other type of atom is available, they bond with another atom of the same type. These are called DIATOMIC MOLECULES.  They are: H 2, O 2, F 2, Br 2, I 2, N 2, Cl 2

12. Common Gases http://patti-isaacs.com/portfolio/ Air is a mixture of gases: Nitrogen (N 2 ) Oxygen (O 2 ) Argon (Ar) Carbon dioxide (CO 2 ) Hydrogen (H 2 ) Ammonia (NH 3 ) Methane (CH 4 )

13. ‘Gas has Mass’ 1.At your station there are two balloons filled with different gases (balloon A & balloon B). A.Make observations about the following variables in both balloons: (1) Volume (is one balloon bigger, or are they about the same?) (2) Temperature (3) Pressure 2.Hold balloons A & B at shoulder height and release. B.What happens to each balloon? C.What can you conclude about the density of each balloon (remember, D=m/V) compared to the density of the gas in the room? 3.Find the mass of balloons B & C on the scale. D.Does gas have mass? Support your response with your observations.

14. Graham’s law (of effusion) Effusion – when a gas escapes through a tiny hole in its container States that the rate of effusion of a gas is inversely proportional to the square root of the gas’s (molar) mass. What you need to know: lighter gases travel faster than heavier gases. The bottom (decimal) number on the periodic table is the mass.

15. Temperature Temperature: measure of the average kinetic energy of each particle within an object. Gases at the same temperature have the same kinetic energy. Kinetic energy = ½(mv 2 )

16. Thermal Equilibrium Two physical systems are in thermal equilibrium if no heat flows between them when they are connected by a path permeable to heat. The arrows represent the relative movement of the particles (circles).

17. Temperature ▫ Kelvin scale: sets 0 as the temperature at which no more energy can be removed from matter and all motion stops. ▫ absolute zero- 0 on Kelvin scale; written as 0K absolute zero ▫ No negative Kelvin temps ▫ For all gas law problems, the temp must be in KelvinKelvin

18. Temperature K = C° + 273 Convert the following temperatures into Kelvin: a. 43 o C b. –135 0 C Convert the following temperatures into Celsius: a. 340 K b.30 K Hint: c to k, add k to c, subtract

19. Kinetic Molecular Theory 1.Gases consist of tiny particles (atoms or molecules). 2.These particles are so small, compared with the distances between them that the volume (size) of the individual particles can be assumed to be negligible (zero). 3.The particles are in constant random motion, colliding with the walls of the container. These collisions with the walls cause the pressure exerted by the gas. 4.The particles are assumed to not attract nor repel each other. 5.The average kinetic energy of the gas particles is directly proportional to the Kelvin temperature of the gas.

20. Pressure http://www.wisegeek.com/what-is-a-pressure- gauge.htm Measures the force of particles hitting the container per unit area Which has more pressure? Why? AB

21. Pressure The metric unit for measuring pressure is ATMOSPHERE (atm). Other units for measuring pressure: mm of Hg (millimeters of mercury) 760 mm Hg = 1 atm kPa (kilopascals) 101.3 kPa = 1 atm psi (pounds per square inch) 14.7 psi = 1 atm

22. How to convert between pressure units Convert 795 mm Hg into atmospheres. 1)Identify conversion factor. 760 mm Hg = 1 atm 2)Set up a dimensional analysis problem a series of fractions First fraction is number you started with over 1 Second fraction is the conversion factor Units you started with should go at bottom of second fraction 795 mm Hg 1atm_____ = 1 760 mm Hg 3)Solve the problem and cancel units (795)(1) = 795 = 1.05 atm (1)(760) 760

23. Pressure conversions – guided practice 1. The air pressure for a certain tire is 109 kPa. What is this pressure in atmospheres?

24. Pressure conversions – independent practice 1. The air pressure inside a submarine is 0.62 atm. What would be the height of a column of mercury balanced by this pressure? 2. The weather news gives the atmospheric pressure as 1.07 atm. What is this atmospheric pressure in mm Hg? 3. An experiment at Sandia National Labs in New Mexico is performed at 758.7 mm Hg. What is this pressure in atm? 4. A bag of potato chips is sealed in a factory near sea level. The atmospheric pressure at the factory is 761.3 mm Hg. The pressure inside the bag is the same. What is the pressure inside the bag of potato chips in kPa? 10 minutes

25. Atmospheric pressure Atmospheric pressure is the result of collisions of air molecules with objects. Atmospheric pressure decreases with an increase in altitude. The air around the earth “thins out” at higher elevations. Which has more pressure exerted on it? (www.naval-technology.com) (ghccprimetimers.org)

26. Atmospheric Pressure decreases with increasing altitude. (hendrix2.uoregon.ed u) 1 atmosphere is defined as the air pressure at sea level.

27. Measuring air pressure Barometers used to measure atmospheric pressure (weather reports) Manometers used to measure the pressure of other gases as compared to atmospheric pressure

28. STP Standard Temperature and Pressure O°C 1 atm

29. Relationships Direct Relationship: when changing one variable causes the other variable to change in the same direction when one goes up, the other goes up; when one goes down, the other goes down

30. Relationships Inverse Relationship: when changing one variable causes the other variable to change in the opposite direction when one goes up, the other goes down Another word for inverse is indirect.

31. Boyle’s law Demo – marshmallows and vacuum pump Independent variable:_______________________ Dependent variable: ________________________ Observations: ____________________________________________ ________________________________________ Relationship: ______________________________

32. Boyle’s Law Boyle’s Law states that gas pressure is inversely proportional to volume at constant temperature and number of particles of gases. ▫ Mathematical relationship: P 1 V 1 = P 2 V 2 This means “pressure one times volume one equals pressure two times volume two)

33. How does Boyle’s Law explain this? A was balloon inflated in San Diego, CA and then taken to Denver, CO (www.faculty.sdmiramar.edu )

34. Explain how these represent Boyle’s law? ffden-2.phys.uaf.edu A.B. (www.chemwiki.ucdavis.edu) Pressure gauge syringe

35. Boyle’s Law Example: A gas has a volume of 100 ml when the pressure is 1.4 atm. What is the volume, in mL, when the pressure is increased to 1.6 atm and the temperature is held constant?

36. If a gas has a volume of 100 ml when the pressure is 1.4 atm, what is the volume, in mL, when the pressure is increased to 1.6 atm and the temperature is held constant? 1. List variables: ▫ V 1 = 100 mL ▫ P 1 = 1.4 atm ▫ V 2 = ? mL ▫ P 2 = 1.6 atm 2. Write formula: ▫ P 1 V 1 = P 2 V 2 3. Substitute in known values: ▫ (100mL)(1.4atm) = (V 2 )(1.6atm) 4. Rewrite without units. (100)(1.4) = (V 2 )(1.6) If desired, switch the sides… (V 2 )(1.6) = (100)(1.4) If desired, switch the unknown and number… (1.6)(V 2 ) = (100)(1.4) 5. Solve for unknown: ▫ Combine terms (1.6)(V 2 ) = 140 ▫ Isolate the variable ▫ (1.6)(V 2 ) = 140 1.6 1.6 ▫ V 2 = 87.5 mL Very Important: Check to see if your answer makes sense… pressure increased by a little (1.4 to 1.6) so volume should decrease by a little (100 to 87.5).

37. L-level Boyle’s Law Guided practice: The volume of a quantity of a gas held at constant temperature and 1.00 atm of pressure is 100. mL. What pressure does it take to reduce the volume to 95 mL?

38. K-level Boyle’s Law Guided Practice: The pressure of a balloon is 101 kPa. What is the new pressure of a balloon after its volume is changed from 502 mL to 301 mL?

39. K-level Boyle’s Law Independent Practice: 1.A gas tank holds 2785 L of propane (C 3 H 8 ) at 830. mm Hg. What is the volume of the propane at standard pressure? 2. A sample of neon (Ne) occupies a volume of 85.0 mL at STP. What will be the volume of the neon when the pressure is reduced to 65.5 kPa? 3. 352 mL of chlorine (Cl 2 ) under a pressure of 680. mm Hg are transferred in a 450. ml container. The temperature remains constant at 296 K. What is the pressure of the gas in the new container? 10 minutes

40. Charles’ law Demo – balloons Independent variable:_______________________ Dependent variable: ________________________ Observations: ___________________________________________________________ ___________________________________________________________ ________ Relationship: ______________________________

41. Charles’ Law The volume of a given amount of gas varies directly to its kelvin temperature when pressure is constant. Mathematical relationship: V 1 = V 2 T 1 T 2 This means “volume one divided by temperature one equals volume two divided by temperature two)

42. Charles’ Law

43. cfbt-us.com

44. Charles’ Law example A balloon inflated in an air conditioned room at 27◦C has a volume of 4.00 L. If it is heated to 57◦C and the pressure remains constant, what is the new volume?

45. 1. List variables and Convert temp to Kelvin: ▫ T 1 = 27°C + 273 = 300 K ▫ V 1 = 4.00 L ▫ T 2 = 57°C + 273 = 330 K ▫ V 2 = ? L 2. Write formula: ▫ V 1 = V 2 T 1 T 2 3. Substitute in known values: (4.00L) = (V 2 )_ (300K) (330K) 4. Rewrite without units ▫ (4.00) = (V 2 )_ (300) (330) Cross multiply… (4.00)(330) = (300)(V 2 ) Combine terms… 1320 = (300)(V 2 ) If desired, switch sides… (300)(V 2 ) = 1320 Isolate variable… (300)(V 2 ) = 1320 300300 5. Solve for unknown : V 2 = 4.4 L 6. Check to see if your answer makes sense… temp went up by 10%, volume went up by 10%.

46. L-level Charles’ law guided practice: A gas kept at constant pressure has a volume of 10.0 L at 25.0° C. At what Celsius temperature would the gas have a volume of 20.0 L?

47. K-level Charles’ law practice: A container holds 50.0 mL of nitrogen at 25° C and a pressure of 736 mm Hg. What will be its volume if the temperature increases by 35° C?

48. Gay-Lussac’s law Demo – crush the can Independent variable:_______________________ Dependent variable: ________________________ Observations: ___________________________________________________________ _________________________ Relationship: ______________________________

49. Gay Lussacs Law The pressure of a gas varies directly to the Kelvin temperature of the sample, if the volume remains constant. ▫ Mathematical relationship P 1 = P 2 T 1 T 2 This means “pressure one divided by temperature one equals pressure two divided by temperature two)

50. Gay-Lussac’s law

51. Gay Lussac’s Law cfbt-us.com

52. Graph of Gay-Lussac’s Law (direct relationship)

53. Gay-Lussac’s Law example A gas in an aerosol can is at a pressure of 1.00 atm and 27.0 o C. If the can is thrown into a fire, what is the internal pressure of the gas when the temperature reaches 927 o C?

54. List variables Convert temp to Kelvin: P 1 = 1.00 atm T 1 = 27°C + 273 = 300 K P 2 = ? atm T 2 = 927°C + 273 = 1200 K Write formula: ▫ P 1 = P 2 T 1 T 2 Substitute in known values: ▫ (1.00atm) = (P 2 ) (300K) (1200K) Rewrite without units… (1.00) = (P 2 ) (300) (1200) Cross-multiply… (1.00)(1200) = (300)(P 2 ) Combine terms… 1200 = (300)(P 2 ) If desired, switch sides… (300)(P 2 ) = 1200 Isolate variable… (300)(P 2 ) = 1200 300 300 Solve for unknown: ▫ P 2 = 4.00 atm Check to see if your answer makes sense…temp quadrupled, pressure quadrupled.

55. Gay- Lussac’s law guided practice: A sample of a gas has a pressure of 851 mm Hg at 285°C. To what Celsius temperature must the gas be heated to double its pressure if there is no change in the volume of the gas?

56. Real-world application Car tire pressure should be measured when the tires are warm after it has been driven. Why? http://www.racintoday.com/archives/3 9412

57. Real-world application This tanker was steam cleaned on the inside, then closed. Why did it implode? http://jmfs1.ortn.edu/myschool/DHundermark/jms8bscience/index _testpage.html

58. Real-world application Why do aerosol cans have a warning to not incinerate them (put them in fire)? http://www.sunlive.co.nz/news/26907-explosion-and-fire- warning.html

59. K-level only: Combined Gas Law Use when p, t, and v all change Temperature must be in Kelvin

60. Combined Gas Law practice A 25.0 ml balloon at 1.20 atm and 45 o C, what is the temperature (in Celsius) of the gas when the volume changes to 100.0 mL and the pressure is 0.816 atm?

61. A 25.0 ml balloon at 1.20 atm and 45 o C, what temperature would the gas be when the volume changes to 100 mL and the pressure is 0.816 atm? 1. List variables 2. Convert temp to Kelvin: ▫ V 1 = 25.0 mL ▫ P 1 = 1.20 atm ▫ T 1 = 45°C + 273 = 318 K ▫ T 2 = ? K ▫ V 2 = 100 ml ▫ P 2 = 0.816 atm 3. Write formula: ▫ P 1 V 1 = P 2 V 2 T 1 T 2 4. Substitute in known values: (1.20atm)(25.0mL) = (0.816atm)(100mL) (318K) (T 2 ) 5. Rewrite without units (1.20)(25.0) = (0.816)(100) (318) (T 2 ) Combine terms… 30 = 81.6 318 T 2 Cross multiply… (30)(T 2 ) = (318)(81.6) Combine terms… (30)(T 2 ) = 25948.8 Isolate variable… (30)(T 2 ) = 25948.8 30 30 6. Solve for unknown ▫ T 2 = 865 K 6. Check to see if your answer makes sense… volume increase is more than pressure decrease, so net result should be that temp increases

62. Combined gas law practice: A sample of gas is stored in a 500.0 mL flask at 1.07 atm and 10.0 o C. The gas is transferred to a 750.0 mL flask at 21.0 o C. What is the new pressure in the flask?

63. IDEALIDEAL VS. REAL GASES Ideal gases don’t really exist, but many gases do behave ideally under certain conditions (far apart and not able to attract each other). Ideal behavior occurs when the Pressure is ______________ Temperature is __________ Mass is ___________ Volume is ____________ Molecules are nonpolar.

64. 1.Which would act more ideally? a)He(g) b)H 2 O(g) Why? 2.Does helium act more ideally at: a)800K b)80K Why? 3.Does helium act more ideally at: a)20.0 atm b)1.00 atm Why?

65. Ideal Gas Law relates Pressure Volume Temperature number of moles(n) For a gas at STP, moles(n) and volume (v) are DIRECTLY related. 1 mole = 22.4 L at STP This is called “molar volume” We haven’t used this variable yet!

66. READ ONLY, DO NOT COPY!!!!!! For any ideal gas, the ratio VP is constant. nT We call this ratio R, the ideal gas constant. Using standard temp and pressure conditions, we can calculate the value of R. R = (22.4L)(1atm) (1mol)(273K) R = 0.0821 L atm/mole K ▫ Because of the units on R, P must be in atm, V must be in L, and T must be in K. Since R is a constant, we will never be solving for it. Rearrange R = VP nT to PV = nRT PV = nRT (pronounced “pivnert”) is called the ideal gas law equation

67. Ideal Gas Law practice What volume would 1.41 moles of oxygen occupy at 351K and 2.30 atm?

68. 1. List variables 2. Convert temp to Kelvin: ▫ V = ? ▫ n = 1.41 moles ▫ T = 351 K ▫ P = 2.30 atm ▫ R = 0.0821 L atm/mol K 3. Write formula: PV = nRT 4. Substitute in known values: (2.30atm)(V) = (1.41mol)(0.0821Latm/molK)(351K) Rewrite with no units… (2.30)(V) = (1.41)(0.0821)(351) Combine terms… 5. Solve for unknown: Combine variables, then divide to get v by itself. V = 17.7 L

69. Ideal gas law practice: What temperature, in Celsius, would 6.00 moles of Helium occupy in a 25.0 L container at 1.26 atm?

70. Independent Practice (10 min) 1.Calculate the pressure (in atm) of a 212 Liter tank containing 23.3 mol of argon gas at 25°C? 2. At what temperature would 2.10 moles of N 2 gas have a pressure of 1.25 atm and in a 25.0 L tank? 3. What volume is occupied by 5.03 g of He at 28°C and a pressure of 0.998atm? 4. A 5000. L weather balloon contains 10.0 moles of He gas. What is the pressure (in atm) when the balloon rises to a point where the temperature is -10.0°C and the gas has completely filled the balloon.

71. Avogadro’s Principle Equal volumes of gases at the same temperature and pressure contain the same number of molecules. *** The type of gas doesn’t matter.*** V 1 = V 2 n 1 n 2

72. Avogadro’s principle example: 72 Relationship between n and V Increased number of gas particles Increased number of collisions with the walls of the container Increased total force of collisions Inside pressure greater than outside pressure Container expands

73. Avogadro’s Law At STP, one mole of a gas occupies a volume of 22.4 L. 1.0 mol of gas or 6.02 x 10 23 particles 22.4 L container

74. Which container has the most gas particles? 2 L 1 atm 3 L 0.5 atm 5 L 0.20 atm All containers are at the same temperature. A B C

75. Compare Properties of Three States of Water ShapeVolumeParticle Diagram Ice (solid) Water (liquid) Air (gas) You have seen water in its three common states of matter before: solid (ice), liquid (water), and gas (steam or water vapor). However, have you ever thought about how the water particles are changing between these three states? You will investigate the physical and chemical properties of water in its different states. For your observations of the shape and volume, they can be either definite or not definite. Observe the ice cubes in their beaker. 1.Do the cubes have a definite shape or do they take the shape of their container? 2.Do the cubes have a definite volume or can the ice be compressed? Observe the liquid water in its beaker. 1.Do the water molecules have a definite shape or do they take the shape of their container? 2.Do the water molecules have a definite volume or can they be compressed? Observe the beaker full of air. In Houston we have enough humidity that there are actually quite a lot of gaseous water molecules in that beaker. 1.Do the water and air particles have a definite shape or do they take the shape of their container? 2.Do the water and air particles have a definite volume or can they be compressed?

76. Compare the compressibility of the three states of matter using syringes 123 Observed Compressibility Inferred Space Between Particles Particle Diagram Sand (solid) Water (liquid) Air (gas) Plunger  Compressibility tells scientists how close together particles are to each other and how much closer they can be squeezed together. You will compare the relative amount of compressibility for samples in different states of matter. Gently push in the plunger of the syringe containing sand. Gently push in the plunger of the syringe containing water. Gently push in the plunger of the syringe containing air. 1)Record your observations ranking the syringes as the most, middle, or least compressible samples. 2)When scientists discuss compressibility, they are determining how much closer together particles can get to each other. Based on this knowledge, infer whether the samples had the most, middle, or least space between the particles. 3)For the particle diagrams, sketch the end of the syringe containing the samples and how close together or far apart the particles are for each sample before being compressed by the plunger.

77. ‘Holey Bottle’ 1.Cover the hole near the bottom of the bottle with your finger, then fill the bottle with water. 2.Without removing your finger, tighten the cap on the water bottle. A.Make a prediction of what the water will do when the finger is removed from the hole. 3.Remove your finger and observe the water in the bottle. B.Do your observations match your prediction? 4.Twist the cap on and off the water bottle. C.How does the water react differently to the cap being on and off the bottle? D.Based on your knowledge of the air pressure inside and outside of the bottle, why doesn’t the bottle leak when the cap is on?

78. ‘Broken Straw?’ 1.Fill the cup partially with water. 2.A student will try to use two straws to drink the water simultaneously – one straw inside the cup of water, the other outside the cup of water. A.Make a prediction about what will happen when the student tries to drink with both straws simultaneously. 3.Have a student volunteer try to use both straws simultaneously to drink water out of the cup. B.Do your observations match your prediction? C.Based on your knowledge of the properties of gases and liquids, why does the student not drink any water? 4.Throw the used straws in the trash.