1. Chapter 14: Solids, Liquids, and Gases
14.1: Matther & thermal energy / Kinetic Theory
14.2: Properties and Fluids
14.3: Behavior of Gases

2. 14.1
Kinetic Molecular theory [KMT] is an explanation of how particles in matter, usually gases, behave.
Matter can exist as solid, liquid, or gas
There is a fourth state of matter, called plasma, that would exist on the sun and other stars.

3. Kinetic Theory All matter is composed of small particles
These particles can be atoms, molecules, or ions
These particles are in constant, random motion. As temperature increases, motion increases
Particles collide with each other and with the walls of container
The particles don’t lose any energy when they collide with each other or container

4. Solid State 1. The particles closely packed together.
2. Have a definite fixed shape and volume (mL)
3. Particles vibrate, but have very little energy

5. Liquid State
What happens to a solid when thermal energy or heat is added to it?
The particles vibrate faster until they have enough energy to overcome the attractive forces liquid
Liquids have a definite, fixed volume. (mL) But they have a shape that takes on their container.

6. Liquid Flow
This extra kinetic energy allows particles to partially overcome the attractions to other particles.

7. Liquid Flow
However, the particles in a liquid have not completely overcome the attractive forces between them
This causes the particles to cling together, giving liquids a definite volume.

8. Gas State
Gas particles have enough kinetic energy to overcome the attractions between them.
2. Do not have a fixed volume or shape.
3. Therefore, they can spread far apart or contract to fill the container that they are in and take the shape of the container

9. Thermal Energy and the Kinetic Theory
Thermal energy- The total energy of a material’s particles
High Temp = High Thermal energy  particles move faster. Most likely a gas
Low Temp = Low Thermal energy  particles move slow. Most likely a solid

10. Average Kinetic Energy
In science, temperature is defined as the average kinetic energy of particles in the substance, or how fast the particles are moving.
We usually say temperature measures how hot or cold something is

11. Average Kinetic Energy
Water molecules at 0°C have lower average kinetic energy than the molecules at 100°C.
Molecules will have kinetic energy at all temperatures, including absolute zero.

12. Liquid State
melting point - temperature at which a solid becomes a liquid.
The melting point value is the same as the freezing point value. Freezing is the reverse of melting.
For example, ice melts at ______ and water freezes at _____ . Ice is solid and water is liquid.
Heat of fusion is the energy required to change something from solid to liquid at its melting point.

13. Gas State
Vaporization- particles are moving fast enough to escape the attractive forces
Vaporization can occur in two ways: evaporation and boiling.
Condensation is the reverse of vaporization.
Evaporation occurs at any temperature, but boiling occurs at a specific temperature at a specific pressure.

14. Gas State
Boiling point - Temperature at which the liquid starts to boil.
The boiling point is better defined as the temperature when pressure of the vapor equals the pressure of the air. Liquids can boil with no heat at a low pressure
Heat of vaporization – energy required for a liquid to turn into a gas at its boiling point.

15. Sublimation
Sublimation is the process of a solid changing directly to a gas without melting and forming a liquid.
Example: dry ice is solid carbon dioxide.

16. Heating curves
A heating curve will graph temperature on the y axis and time on the x axis and show the temperature changes as thermal energy is added to something.
Flat lines indicate the melting and boiling points

17. Heating curve for water

18. plasma
Plasma
very high KE - particles collide with enough energy to break into charged particles (+/-)
gas-like, indefinite shape & volume
stars, fluorescent light bulbs, TV tubes

19. Expansion of Matter
Particles move faster and separate as the temperature rises. This separation of particles results in an expansion of the entire object, known as thermal expansion.
Thermal expansion –Increase or decrease in the size of a substance when the temperature is increased or decreased.

20. Thermal Expansion
Liquids in thermometers expand as they get hotter. The liquid particles move faster and it rises as it expands.
Have you noticed the seams in a concrete driveway or sidewalk?
These separation lines are called expansion joints.

21. Expansion in Gases
Hot-air balloons are able to rise due to thermal expansion of air.
The air in the balloon is heated, causing the distance between the particles in the air to increase.

22. Expansion in Gases
As the hot-air balloon expands, and becomes less dense causing the balloon to rise

23. Expansion of Matter
Increase Temp  Increased particle movement Increase in sizes
Decrease Temp Decrease particle movement Decrease in size

24. Heating curves Evaporation Condensation
liquid to gas below the boiling point ; occurs at any temperature.
BOILING is the temperature at the flat line
Condensation
gas to liquid
Can occur at any temperature
Also occurs opposite of boiling

25. Strange behavior of water
Freezing water molecules
unlike charges are attracted to each other and line up so that only positive and negative zones are near each other.
water molecules orient themselves according to charge, empty spaces occur in the structure.
these empty spaces are larger in ice than in liquid water, so water expands when going from a liquid to a solid state.

26. Solid or a Liquid?
Amorphous solids and liquid crystals [amorphous means “without shape”]
two classes of materials don’t react as expected when changing states.
solids soften and gradually turn into a liquid over a temperature range
lack the highly ordered structure found in crystals
are typically long, chainlike structures that can get jumbled and twisted

27. Liquid Crystal Displays
LCD
flow during the melting phase similar to a liquid, but they do not lose their ordered arrangement completely.
placed in classes depending upon the type of order they maintain when they liquefy
are highly responsive to temperature changes and electric fields.
ex: televisions, watches, clocks, and calculators

28. Question 1 What are the four assumptions of the kinetic theory?
Section Check
Question 1
What are the four assumptions of the kinetic theory?

29. Answer 16.1 The four assumptions are:
Section Check
16.1
Answer
The four assumptions are:
all mater is composed of small particles
these particles are in constant random motion,
these particles are colliding with each other and with the walls of their containers
no loss of energy when particles collide

30. Section Check
Question 2
What is the difference between thermal energy and temperature?

31. Section Check
Answer
Thermal energy is the total amount of kinetic and potential energy of a materials’ particles; temperature is a measure of the average kinetic energy of a material’s particles.

32. Section Check
Question 3
The energy required to change a solid to a liquid __________.
boiling point
heat of fusion
heat of vaporization
melting point

33. Section Check
Answer
The answer is D. The heat of fusion is the amount of energy required; melting point is a temperature.

34. Section 2: Properties of fluids
A fluid is a gas or a liquid; they have no fixed shape and can flow easily
despite their weight ships are able to float.
greater force pushing up on the ship opposes the weight—or force—of the ship pushing down.

35. How do ships float? 16.2 Despite their weight ships are able to float.
Properties of Fluids
16.2
How do ships float?
Despite their weight ships are able to float.

36. Properties of Fluids
How do ships float?
Buoyancy is the ability of a fluid—a liquid or a gas—to exert an upward force on an object immersed in it.
If the buoyant force is equal to the object’s weight, the object will float.
If the buoyant force is less than the object’s weight, the object will sink.

37. Properties of Fluids
Archimedes’ Principle: states that buoyant force on an object is equal to the weight of the fluid displaced by the object. It is named for a Greek man from the 3rd century BC
Ex: if a block of wood is put in water, it will push water away as it sinks, but only until the weight of the water displaced equals the block’s weight. The wood floats because the water weight equals the weight of the wood.

38. Ex: if a block of steel is put in water, it will push water away as it sinks, and the steel weighs more than the amount of water displaced. The steel sinks because the water weight is less than the weight of steel.

39. Archimedes’ Principle
Buoyant Force and gases
Buoyant force is the upward force exerted by a fluid on an immersed object
buoyant force is greater than weight
balloon rises
buoyant force is less than weight
balloon sinks
buoyant force = weight
balloon floats

40. Properties of Fluids
Density
This ship floats because it’s overall density is less than water’s (1g/mL) due to all of the air.

41. Pascal’s Principle and Pressure
Properties of Fluids
Pascal’s Principle and Pressure
Blaise Pascal ( ),
a French scientist, discovered a useful property of fluids.
Pascal’s Principle- pressure applied to a fluid is transmitted throughout the fluid.
pressure applied to a fluid is transmitted unchanged throughout the fluid
Pressure at point 1 = pressure at point 2
Examples: toothpaste, hydraulic lifts

42. Properties of Fluids
Pascal’s Principle

43. Pressure Pressure is defined as force exerted per unit area
Pressure formula
Units
Pressure is in pascals (Pa) or pounds per square inch (PSI)
Force is in newtons (N) or pounds (lbs)
Area is in square meters (m2) or square inches (in2)
A pascal is the same as a newton per square meter (Pa = N/m2)

44. Applying the Principle
pipe filled with fluid connects small and large cylinders.
pressure applied to the small cylinder is transferred through the fluid to the large cylinder

45. Applying the Principle
pressure remains constant throughout the fluid
more force is available to lift a heavy load by increasing the surface area.

46. View hydraulics explanation.
Pascal’s Principle
Pascal’s Principle – variations
The 1’s are one object and the 2’s are another object
View hydraulics explanation.

47. units
Force is in POUNDS (English system) or NEWTONS (metric SI system)
One pound is 4.45 newtons
One kg I = 9.8 newtons = 2.2 pounds
Area is in square meters or square inches or square centimeters (any length squared)
Pressure is in Pascals [Pa]
1 Pa = 1 N/m2

48. Pascal’s Principle Platform: F = 1000 N A = 250 m2 Plunger: F = ?
A car weighing 1000 N sits on a 250 m2 platform. What force is needed on the 10 m2 plunger to keep the car from sinking?
GIVEN:
Platform:
F = 1000 N
A = 250 m2
Plunger:
F = ?
A = 10 m2

49. Pascal’s Principle Platform: F = 1000 N A = 5 m2 Plunger: F = ?
A disgruntled cow that weighs 1000 N sits on a 5 m² piston. What force would need to be applied to a 2 m² piston?
GIVEN:
Platform:
F = 1000 N
A = 5 m2
Plunger:
F = ?
A = 2 m2

50. Pascal’s principle
A bicycle pump has a piston with area of m2. How much force is needed to create a pressure of 730,000 Pa?

51. Do problems : page 443, numbers 8,9,10 and page 444 numbers 11 and 12

52. A car weighing 15,000 Newtons is on a hydraulic lift measuring 10 m2
A car weighing 15,000 Newtons is on a hydraulic lift measuring 10 m2. What is the area of the smaller piston if a force of 1,100 Newtons is used to lift the car?
If the car tires cover an area of m2, what is the pressure in the car tires?
What is the weight of the car in pounds?

53. Bernoulli’s Principle
Properties of Fluids
Bernoulli’s Principle
Bernoulli’s principle- as the velocity of a fluid increases, the pressure exerted by the fluid decreases.
Examples: airplane lift, curve balls

54. Bernoulli’s Principle
demonstrate Bernoulli’s principle
blow across the top surface of a sheet of paper.
What happens to the paper?
The paper will rise
Velocity of the air over the top is greater than that of the quiet air below it.
Net force below raises the paper

55. Bernoulli’s Principle
Airplane lift
The downward force decrease and
the lifting force increases.
Bernoulli’s
principle states that as the velocity
of a fluid increases the pressure exerted
by the fluid decreases.

56. Bernoulli’s Principle
Venturi Effect - Atomizers
is the reduced fluid pressure that results when a fluid flows through a constricted section of a pipe.
The Venturi effect is named after Giovanni Battista Venturi (1746–1822), an Italian physicist.

57. Bernoulli’s Principle
Venturi Effect
fluids flow faster through narrow spaces causing reduced pressure
EX: garden sprayer, atomizer (see page 445)

58. Venturi effect
This allows the water in the hose to flow at a high rate of speed, creating a low pressure area above the strawlike tube.
The concentrated chemical solution is sucked up through the straw and into the stream of water.
The concentrated solution is mixed with water, reducing the concentration to the appropriate level and creating a spray that is easy to apply.

59. Viscosity is resistance to flow by a fluid.
Properties of Fluids
Viscosity is resistance to
flow by a fluid.
Ex: motor oil and maple syrup are very viscous
When a container of liquid is tilted to allow flow to begin, the flowing particles will transfer energy to the particles that are stationary, pulling those particles too.
Temperature and viscosity are inversely related; that is higher temperature means lower viscosity

60. High viscosity= Low Flow, Thick Low viscosity= High flow, Thin
Properties of Fluids
flowing particles are pulling the other particles, causing them to flow
If the flowing particles do not effectively pull the other particles into motion, then the liquid has a high viscosity, or a high resistance to flow. Ex: maple syrup.
If the flowing particles pull the other particles into motion easily, then the liquid has low viscosity, or a low resistance to flow. Ex: water
High viscosity= Low Flow, Thick
Low viscosity= High flow, Thin

61. Section Check
16.2
Question 1
If the buoyant force on an object in a fluid is less than the object’s weight, the object will ___________.
A. be propelled forward
B. expand
C. float
D. sink

62. Section Check
16.2
Answer
The answer is D. Buoyancy is the ability of a fluid to exert an upward force on an object immersed in it.

63. Section Check
16.2
Question 2
Why can a steel ship float in water if a steel block with the same mass sinks?

64. Section Check
16.2
Answer
The reason the steel ship can float is because its mass takes up a larger volume, so its density is less than that of the steel block, and less than the density of water.

65. Section Check
16.2
Question 3
According to Pascal’s principle, __________ applied to a fluid is transmitted throughout the fluid.
A. density
B. pressure
C. temperature
D. volume

66. Section Check
Answer
The answer is B. Pressure is a force exerted per unit area. Pressure applied to a fluid is transmitted throughout the fluid

67. Section 14.3 – Behavior of gases
Boyles Law – describes the relationship between gas pressures and the volume (size) of an object
Think of a balloon:
What happens when it goes up high in the atmosphere?

68. Boyle’s Law – Volume and Pressure
Behavior of Gases
Boyle’s Law – Volume and Pressure
Pressure is the amount of force exerted per unit of area, or
P = F/A.
They remain inflated because of collisions the air particles have with the walls of their container.

69. Pressure 16.3 Pressure unit is Pascal (Pa) or Kilopascal (kPa)
Behavior of Gases
16.3
Pressure
Pressure unit is Pascal (Pa) or Kilopascal (kPa)
1 Pascal = 1 Newton per square meter or
1 N/m2

70. Pressure 16.3 At sea level, atmospheric pressure is 101.3 kPa.
Behavior of Gases
16.3
Pressure
At sea level, atmospheric pressure is kPa.
At Earth’s surface, the atmosphere exerts a force of about 101,300 N on every square meter—about the weight of a large truck.

71. Boyle’s Law Boyle’s law-
Behavior of Gases
Boyle’s Law
Boyle’s law-
Decrease size of container Increases Pressure
Increase size of container Decrease Pressure
***Temperature must remain constant***

72. Behavior of Gases
16.3
Boyle’s Law

73. P1V1 = P2V2. Boyle’s Law formula
Behavior of Gases
Boyle’s Law formula
P1V1 = P2V2.
P- pressure in container in Pa or kPa or N/m2
V- volume in container in mL, or L, or cm3 or dm3
1’s are starting conditions
2’s are ending conditions

74. Behavior of Gases
example
A weather balloon has a volume of 100 L at sea level where the pressure is 101 kPa. What would be the volume up in the air where pressure is 43 kPa?

75. Behavior of Gases
example
A helium balloon measures 2.52 liters at a pressure of 15 pascals. What pressure would be needed to reduce its volume to 1.52 liters?

76. Behavior of Gases
example
A hot air balloon is at 99 kPa on the ground and measures 125 liters. What volume is it in the air at 72 kPa?

77. Behavior of Gases
example
A student blows up a balloon to be 550 cm3 at 98 kPa. What pressure is needed to increase it to 750 cm3?

78. Behavior of Gases
16.3
Charles’s Law
Charles’s law- Volume of a gas increases with increasing temperature, as long as pressure does not change

79. High an low temperatures were extrapolated from a graph
Behavior of Gases
High an low temperatures were extrapolated from a graph
To extrapolate means to extend the graph beyond what was measured.

80. What happens to a balloon if heated or cooled?

81. V1/T1 = V2/T2 Using Charles’s Law V- Volume of gas in Liters
Behavior of Gases
Using Charles’s Law
V1/T1 = V2/T2
V- Volume of gas in Liters
T- Temperature of gas in Kelvin
The pressure must be the same
Temperature MUST BE in Kelvin ( K = C° + 273)

82. Section Check
Question 1
Compare Boyle’s law to Charles’ law.

83. Section Check
16.3
Answer
Boyle’s law relates the pressure of a gas to its volume at constant temperature. As volume increases, the pressure decreases; the reverse is also true. Charles’ law relates the volume of a gas to its temperature at a constant pressure. As the temperature of a gas increases, its volume also increases.

84. Section Check
16.3
Question 2
What would be the resulting volume of a 3.0-L balloon at 25.0º C that was placed in a container of ice water at 4.0º C, if pressure is constant?
A L
B L
C L
D L

85. Section Check
16.3
Answer
The answer is A. Use the formula that relates volume to temperature given in Kelvin, V1/T1 = V2/T2. In this case, V1 = 3.0 L, T1 = 25.0º C = 298º K, T2 = 4.0º C = 277º K. Solving for V2 gives 2.8 L.

86. Question 3 The SI unit of pressure is the __________, which is N/m2
Section Check
Question 3
The SI unit of pressure is the __________, which is N/m2
A. coulomb
B. tesla
C. Watt
D. pascal

87. Section Check
16.3
Answer
The answer is D. The SI unit of pressure is the Pascal; pressures are often given in kilopascals.

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