1. Bell Ringer
What is the difference between the different states of matter?
[in terms of energy or particles]

2. Kinetic
Molecular
Theory

3. The Kinetic Molecular Theory
based on the idea that particles are constantly moving
can be applied to solid, liquid, or gas
provides a model of ideal gas behavior so it is only an approximation
Ideal student
Real student vs

4. 1. Gases consist of tiny particles that are very far apart
most volume is empty spacelow density
allows gases to be easily compressed
2. All collisions between particles and container walls are elastic
there is no net loss of energy when particles collide
total kinetic energy stays constant even though it can be transferred between particles

5. 3. Particles are in continuous, rapid, random motion
since they are moving, they have KE
KE overcomes their attractive forces
4. No forces of attraction or repulsion
YOU ARE ATTRACTED TO EVERYTHING!

6. Average kinetic energy depends on temperature
KE increases as temperature increases
At the same T, lighter particles have higher speeds than heavier ones
velocity and temperature are directly proportional

7. REAL Gases vs. IDEAL Gases The most ideal real gases are H and He
ideal gas is defined by the KMT
most gases behave close to the ideal when there is:
HIGH temperature – so they have enough KE to overcome attractive forces
Low pressure – so they are very spread out
Gases with little attraction, low mass, are more ideal (monatomic gases)
The most ideal real gases are H and He

8. Activity
Create a cartoon that helps to explain the KMT to other students!
Grade will be based upon:
Creativity
Effort
Use of color

9. List the 4 parts of the KMT.
Bell Ringer
List the 4 parts of the KMT.

10. Pressure

11. Pressure P : amount of force in an area
Why would shoes with smaller diameter heel not be allowed on gym floor?
As surface area decreases, pressure increases
Pressure exerted by a gas depends on
volume
temperature
number of molecules

12. STANDARD TEMPERATURE & PRESSURE STP
Standard Temperature = 0°C
Standard Pressure = 1 atm

13. Pressure and Temperature
STP
(Standard Temperature and Pressure)
standard temperature
standard pressure
0oC
1 atm
273 K
101.3 kPa
760 mm Hg
Equations / Conversion Factors:
K = oC + 273
oC = K – 273
1 atm = kPa = 760 mm Hg = 760 torr

14. Conversions Convert 25oC to Kelvin. K = oC + 273 25oC + 273 = 298 K
How many kPa is 1.37 atm?
101.3 kPa
X kPa = atm
= kPa
1 atm
How many mm Hg is kPa?
760 mm Hg
X mm Hg = kPa
= mm Hg
101.3 kPa

15. Practice Conversions

16. Vapor Pressure
Is the pressure of the vapor over a liquid (and some solids) at equilibrium
Must be in contact with a liquid otherwise you just have a gas!
Depends on temperature only

17. NOT all liquids have same vapor pressure at same temp.
measure of the tendency for liquid particles to enter
gas phase at a given temp.
a measure of “stickiness” of liquid particles to each other
more
“sticky”
less likely to
vaporize
In general:
LOW v.p.
not very
“sticky”
more likely to
vaporize
In general:
HIGH v.p.
NOT all liquids have same vapor pressure at same temp.

18. Bell Ringer
If the pressure inside a tire is 248 kPa, how many millilmeters of mercury is that?
1860

19. How Vapor Pressure is Measured
Animation by Raymond Chang
All rights reserved

20. Vapor Pressure manometer
DEMOS
Vapor Pressure manometer

21. Behavior of a liquid in a closed container

22. Table H

23. Boiling Point Explained
100 80
CHLOROFORM
PRESSURE
(kPa) 60
ETHANOL
b.p. = 78oC 40 20
WATER
b.p. = 100oC 20 40 60 80
100
TEMPERATURE (oC)
Volatile substances evaporate easily (have high v.p.’s).
BOILING  when vapor pressure = confining pressure
(usually from atmosphere)
atmospheric pressure is kPa

24. Formation of a bubble is opposed by the pressure of the atmosphere

25. Boiling vs. Evaporation
Boiling point: atmospheric pressure = vapor pressure
AIR
PRESSURE
15psi
Revolutionary process - fast
VAPOR
PRESSURE
15 psi
Lyophilization – freeze drying
Evaporation: molecules go from liquid to gas phase
gas
Evolutionary process - slow
liquid

26. measures atmospheric pressure
Barometer
Empty space
(a vacuum) Hg
Weight of the
mercury in
the column
atmosphere
(atmospheric
pressure)
measures atmospheric pressure

27. Barometers Mount Everest Sea level
fraction of 1 atm
average altitude
(m)
(ft) 1
1/2
5,486
18,000
1/3
8,376
27,480
1/10
16,132
52,926
1/100
30,901
101,381
1/1000
48,467
159,013
1/10000
69,464
227,899
1/100000
96,282
283,076
Barometers
Mount Everest
Every point on Earth’s surface experiences a net pressure called atmospheric pressure.
• Pressure exerted by the atmosphere is considerable.
• A 1.0-m2 column, measured from sea level to the top of the atmosphere, has a mass of about 10,000 kg, which gives a pressure of 100 kPa:
pressure = (1.0 x 104kg) (9.807 m/s2) = 1.0 x105 Pa = 100 kPa
1.0 m2
• In English units, this is 15 lb/in2.
Atmospheric pressure can be measured using a barometer, a closed, inverted tube filled with mercury.
• The height of the mercury column is proportional to the atmospheric pressure, which is reported in units of millimeters of mercury (mmHg), also called torr.
Standard atmospheric pressure is the atmospheric pressure required to support a column of mercury exactly 760 mm tall; this pressure is also referred to as 1 atmosphere (atm).
• A pressure of 1 atm equals 760 mmHg exactly and is approximately equal to 100 kPa:
1 atm = 760 mmHg = 760 torr = x 105Pa = kPa
Pressure varies smoothly from the earth's surface to the top of the mesosphere. Although the pressure changes with the weather, NASA has averaged the conditions for all parts of the earth year-round. The following is a list of air pressures (as a fraction of one atmosphere) with the corresponding average altitudes. The table gives a rough idea of air pressure at various altitudes.
Sea level
Sea level On top of Mount Everest

28. Table H

29. Practice
Vapor Pressure
of 4 liquids
wkst

30. Table H

31. Quiz 1.What is one way you can make a real gas act more ideal?
kPa = _______ mmHg
3. If ethanol boils at 82°C, what is the atmospheric pressure?
4. In terms of pressure(s), when does a liquid boil?
5. Name of the two MOST ideal REAL gases?

32. Quiz 1. Spread out, high temp or low press 2. 691mmHg 3. 110 kPa
4. When vp = atm pressure
5. H or He

33. Bell Ringer
According to Reference Table H, at what temperature will propanone boil if the atmospheric pressure is 70kPa?

34. Evaporation
H2O(g)
molecules
(water vapor)
H2O(l)
molecules

35. DEMOS
Boiling Water
Boiling with dec. VP
With Ice

36. Table H

37. Gas Laws

38. Show how pressure, volume, and temperature, are related to gases.
Gas Laws
Show how pressure, volume, and temperature, are related to gases.
REMEMBER 
P T V

39. The volume must increase!
Gas Laws
Hold whichever variable constant to adjust the other variable to see what would happen as a result of the desired change
If the temperature remains constant and we lower the pressure, what must happen to the volume?
P T V
P T V
The volume must increase!

40. The pressure must increase!
Gas Laws
If the temperature remains constant and we lower the volume, what must happen to the pressure?
P T V
P T V
The pressure must increase!

41. Relationships between volume and pressure.
Boyle's Law
Relationships between volume and pressure.

42. DEMOS
Vacuum Pump

43. Boyle’s Law: P and V as one increases, the other decreases
inversely proportional
pressure is caused by moving molecules hitting container walls
If V is decreased and the # of molecules stays constant, there will be more molecules hitting the walls per unit of time

44. Boyle’s Law

45. Pressure vs. Volume for a Fixed Amount of Gas (Constant Temperature)
Pressure Volume PV
(Kpa) (mL)
,000
,950
,000
,000
,800
,500
,000
,500
600
500
400
Volume (mL)
300
The pressure for this data was NOT at 1 atm.
Practice with this data: (where Pressure = 1 atmosphere)
Volume Temp (oC) (K) V/T
63.4 L
As the pressure on a gas increases, the volume of the gas decreases because the gas particles are forced closer together.
As the pressure on a gas decreases, the gas volume increases because the gas particles can now move farther apart.
Boyle carried out some experiments that determined the quantitative relationship between the pressure and volume of a gas.
Plots of Boyle’s data showed that a simple plot of V versus P is a hyperbola and reveals an inverse relationship between pressure and volume; as the pressure is doubled, the volume decreases by a factor of two.
Relationship between the two quantities is described by the equation PV = constant.
Dividing both sides by P gives an equation that illustrates the inverse relationship between P and V:
V = constant = constant(1/P) or V  1/P P
• A plot of V versus 1/P is a straight line whose slope is equal to the constant.
• Numerical value of the constant depends on the amount of gas used in the experiment and on the temperature at which the experiments are carried out.
• This relationship between pressure and volume is known as Boyle’s law which states that at constant temperature, the volume of a fixed amount of a gas is inversely proportional to its pressure.
200
100
Pressure (KPa)

46. Chucky’s Law (aka Charles Law)
Relationship between volume and temperature

47. Charles’ Law: V and T if P is constant, gases expand when heated
when T increases, gas molecules move faster and collide with the walls more often and with greater force
to keep the P constant, the V must increase

48. Example: Boyle’s Law
Consider a 1.53L sample of gaseous SO2 at a pressure of 5.6 x 103 Pa. If the pressure is changed to 1.5 x 104 Pa at constant temperature, what will be the new volume of the gas?

49. Practice
1. If the volume of a gas at 10.0oC is ml, then what is the volume at -2.0oC?
V1 =V2
T1 T2
T1 = 10oC
100.0 ml V2 =
V1 = mL
10.0oC
-2.0oC
T2 = -2.0oC
10.0 x V2 =
-200
V2 = ?
V2 = -20. ml
We can’t have negative volumes, so we can’t use a temperature scale with negatives
V1 =V2
T1 T2
With gas laws, ALWAYS USE KELVIN
T1 = 10oC
283 K
100.0 ml V2 =
V1 = mL
283 K
271 K
T2 = -2.0oC
271 K
283 x V2 =
27100
V2 = mL
96 mL
V2 = ?

50. Gas Laws pkt
Vapor Pressure wkst

52. Charles’ Law: V and T Animation
Charles’ Law: the V of fixed mass of gas at constant P varies directly with temperature.
What kind of graph is V vs. T?
Animation

53. Son of Early of Cork, Ireland.
Boyle's Law
If n and T are constant, then
PV = (nRT) = k
This means, for example, that
Pressure goes up as Volume goes down.
A bicycle pump is a good example of Boyle's law.
As the volume of the air trapped in the pump is
reduced, its pressure goes up, and air is forced
into the tire.
Robert Boyle
( )
Son of Early of Cork, Ireland.

54. Boyle’s Law As the pressure on a gas increases - the volume decreases
1 atm
As the pressure on a gas increases -
the volume decreases
Pressure and volume are inversely related
As the pressure on a gas increases
2 atm
4 Liters
2 Liters

56. Pressure-Volume Relationship
250
200
150
100 50
0.5
1.0
1.5
2.0
Volume (L)
Pressure (kPa)
(P3,V3)
(P1,V1)
(P2,V2)
P1 = 100 kPa
V1 = 1.0 L
P2 = 50 kPa
V2 = 2.0 L
P3 = 200 kPa
V3 = 0.5 L
2.5
P1 x V1 = P2 x V2 = P3 x V3 = 100 L x kPa

57. P vs. V (Boyle’s Data)

58. Charles’ Law discovered by French physicist, Jacques Charles in 1787
first person to fill balloon with hydrogen gas and make solo balloon flight

59. Example: Charles’ Law & Temp.
A sample of gas at 15.0°C and 1.00 atm has a volume of 2.58 L. What volume will this gas occupy at 38.0°C and 1.00 atm?
V1 =V2
T1 T2
P1 = 1.00 atm
P2 = 1.00 atm
T1 = 15.0oC
= 288K
T2 = 38.0oC
= 311K
V1 = 2.58 L
V2 = ?
2.58 L V2 =
288K
311K
V2 x 288K =
802L*K V2 =
2.79L

60. Bell Ringer
If the pressure on a gas is decreased by ½, how much larger will the volume become?
Which gases makes the most ideal gases real gases?

61. Cooling Curve Review

62. Gas Laws Lab

63. Bell Ringer Balloon #1 contains H2 gas Balloon #2 contains He gas
Four identical balloons contain equal volumes of gas at STP.
Balloon #1 contains H2 gas
Balloon #2 contains He gas
Balloon #3 contains O2 gas
Balloon #4 contains N2 gas
Which balloon would weigh the most? Explain
According to the KMT, why would the balloons expand upon heating?

64. DEMOS
Pressure Cooker

65. Bell Ringer
If you have a basketball that has a volume of 2.2L at a pressure of 3.00atm. What would it’s volume be at Standard Pressure?

66. Let's Practice
A. Increases
As the temperature of a liquid increases, its vapor pressure
A. Increases B. Decreases C. Remains the same
According to Reference Table H, what is the vapor pressure of propanone at 45ºC?
70.0 kPa
What is the name of the of the phase change that turns a solid directly into a gas?
Sublimation
Which liquid on Table H has the strongest intermolecular forces of attraction?
Ethanoic Acid

67. Table H

68. 1 x 1023 Avogadro's Hypothesis
Amadeo Avogadro created two important ideas used in science
1. Hypothesis
If we have two gases with the same temperature and pressure at the same volume, they will have the same number of molecules.
Gases are made of mostly empty space, so the size of the individual molecules does not matter
Example - A sample of H2(g) contains 1 x 1023 molecules at a particular volume at STP. How many molecules of CO2(g) takes up the same volume at STP?
Same T, same P and same V
= same # of molecules
1 x 1023

69. 2. Molar volume of a gas
In chemistry, we use very large numbers of atoms.
So Avagadro created a large unit called -
Mole
= 602,000,000,000,000,000,000,000 objects
Pair = 2
Dozen = 12
Mole =
6.02 x 1023
If we have one mole of ANY gas at standard temperature and pressure, it will take up
22.4 L
of space
Examples
1. How much room does 6.02 x 1023 molecules of N2(g) occupy at STP?
One mole
= 22.4 L
2. How much volume does 0.5 moles of CO2(g) occupy at STP?
11.2L

70. 3. If we have 3.01 x 1023 molecules of CO2(g) at STP, what is the volume?
0.5 moles
11.2 L
4. How many molecules are in 44.8 L of H2S(g) at STP?
2 moles
2 x 6.02 x 1023
1.204 x 1024
5. If we have 9.03 x 1023 molecules of a gas at STP, what is the volume?
1.5 moles
33.6 L

72. Dalton’s Law of Partial Pressure

73. Dalton’s Law of Partial Pressure
the total P of a mixture of gases is equal to the sum of partial P of component gases, no matter how many different gases
PT = P1 + P2 + P3 + …
Partial Pressure- P of each gas in mixture

74. Why?
the particles of each gas in a mixture have an equal chance to hit the walls
so each gas exerts P independent of that exerted by other gases
total P is result of the total # of collisions per unit of wall area

75. Table H worksheet

76. Bell Ringer
According to Reference Table H, which liquid will evaporate more rapidly?
At what temperature does ethanol have the same vapor pressure as propanone at 68.5˚C?

77. Bell Ringer
A gas sample has a volume of 25.0 ml at a pressure of 1.0 atm. If the new volume increases to 50.0 ml and the temperature remains constant, the new pressure will be?

78. Combined
Gas
Laws

79. Combined Gas Laws a gas often changes in T, P, and V all at once
the other gas laws can be combined into one law
Combined Gas Law- relationship between P, V, and T of a fixed amount of gas

80. Combined Gas Laws
Example - A gas is collected at 273 K and 2.00 atm to a volume of 50.0 ml. What is the new pressure of a gas if the temperature drops to K and the volume increases to 75.0 ml?
P1 = 2.00 atm
P2 = ?
V1 = 50 mL
V2 = 75.0 ml
T2 = K
T1 = 273 K
2.00 x 50 ml
P2 x 75.0 ml =
273 K
200.0 K
20,475 x P2 =
20,000
0.977 atm
P2 = atm

81. Combined Gas Laws
A Helium-filled balloon has volume of 50.0 L at 25°C and 1.08 atm. What volume will it have at atm and 10.°C?
P1 = 1.08 atm
P2 = atm
V2 = ?
V1 = 50.0 L
T2 = 10.°C
= 283 K
T1 = 25°C
= 298 K
(1.08 atm)(50.0 L)
(0.855 atm)(V2) =
298 K
283 K
x V2 =
15282
60. L
V2 = L

82. Bell Ringer
Which 5.0 ml sample of NH3 will take the shape of and completely fill a closed ml container?
A. NH3(s) C. NH3(g)
B. NH3(l) D. NH3(aq)

83. Gas Laws and Boyles Problems
Sub
Gas Laws and Boyles Problems

84. Combined
Gas
Laws

85. Bell Ringer
Which sample at STP has the same number of molecules as 5 liters of NO2(g) at STP?
5 grams of H2(g)
5 liters of CH4(g)
5 moles of O2(g)
5 x 1023 molecules of CO2(g)

86. Combined Gas Laws a gas often changes in T, P, and V all at once
the other gas laws can be combined into one law
Combined Gas Law- relationship between P, V, and T of a fixed amount of gas

87. Combined Gas Laws
Example - A gas is collected at 273 K and 2.00 atm to a volume of 50.0 ml. What is the new pressure of a gas if the temperature drops to K and the volume increases to 75.0 ml?
P2 = ?
P1 = 2.00 atm
V2 = 75.0 ml
V1 = 50 mL
T2 = K
T1 = 273 K
2.00 x 50 ml
P2 x 75.0 ml =
273 K
200.0 K
20,475 x P2 =
20,000
0.977 atm
P2 = atm

88. Combined Gas Laws
A Helium-filled balloon has volume of 50.0 L at 25°C and 1.08 atm. What volume will it have at atm and 10.°C?
P1 = 1.08 atm
P2 = atm
V2 = ?
V1 = 50.0 L
T2 = 10.°C
= 283 K
T1 = 25°C
= 298 K
(1.08 atm)(50.0 L)
(0.855 atm)(V2) =
298 K
283 K
x V2 =
15282
60. L
V2 = L

89. Bell Ringer
A 1.00-mole sample of a neon gas occupies a volume of K and kPa. Calculate the density of this sample.
0.827 g/L

90. Jeopardy

92. Exam

93. Bell Ringer
Using Table H, how would you have to adjust your cooking time of pasta high in the mountains?

94. Water rapidly boiling on a stove

95. Water rapidly boiling on a stove

96. Pressure Cooker http://gotethnicfoods.com/pictures/Regular/AGLS020.jpg
Copyright © 2006 Pearson Benjamin Cummings. All rights reserved.

97. 120oC

98. Pressure Cooker http://gotethnicfoods.com/pictures/Regular/AGLS020.jpg
Copyright © 2006 Pearson Benjamin Cummings. All rights reserved.

99. 120oC

100. Bell Ringer
A gas occupies a volume of 560.ml at a temperature of 100.°C. To what temperature must the gas be changed if it is to occupy 400.ml, with the pressure remaining unchanged?

101. Table H

102. Heating / Cooling Curve of Water
140
steam
120
water and steam
100
liquid water 80
Temperature (oC) 60
Heating
Cooling 40
ice and
water 20
ice
-20
Heat added at a constant rate