phases & behavior of matter - jackson county school … and behavior of matter goals 2 1....
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Phases and Behavior of Matter Goals
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1. Compare and contrast the atomic/molecular motion of solids, liquids,
gases & plasmas. 2. Explain the flow of energy in phase changes through the use of a phase
diagram. 3. Relate temperature, pressure, and
volume of gases to the behavior of gases.
Solid Liquid Gas
Review • Everything in the universe is either matter or energy.
• Physical Science is the study of matter and energy.
•Matter is anything that has mass and takes up space.
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1) All matter is composed of small particles (atoms). 2) These particles are in constant motion. 3) These particles are colliding with each other and the
walls of their container.
Kinetic Theory of Matter 4 Clip
Kinetic Energy • Kinetic Energy is the energy of
motion. • Temperature is the measurement of
the KE in an object. • So, the more KE the higher the
temp. • As the particles in an object gain
KE, the temperature goes up.
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Solids • Particles are closely packed together. • Most are geometric. • There are bonds between atoms/mol. • Rigid shapes. • Definite shape. • Definite volume.
6 Clip Amorphous Solids
Liquids
• Particles in a liquid have more KE than
particles in a solid.
• Liquid particles have enough KE to overcome
the forces that hold them together.
• The particles can now move past one another.
(flow)
• Definite volume
• No Definite shape.
7 Clip
Viscosity
Gases • Gas particles have
more KE than liquid particles.
• They have enough energy to break all bonds and escape the liquid state.
• No definite Shape
• No definite Volume. Gases fill their
container.
8 Clip
Plasma o Most common state
of matter in the universe
o Extremely high temperatures.
o Contains positively and negatively charged particles
10.1 Clip
Artificially produced plasmas
•Those found in plasma displays, including TVs
•Inside fluorescent lamps (low energy lighting), neon signs
•The electric arc in an arc lamp, an arc welder or plasma torch
•Plasma ball (sometimes called a plasma sphere or plasma globe)
Terrestrial plasmas
•Lightning
•The ionosphere
•The polar aurorae
10.2
ReviewClip
o Force produced by high energy collisions strips electrons from atoms.
o Sun, lighting bolts, neon and fluorescent tubes, auroras.
TODAY in the computer lab
• PHET Phases of matter
simulation
• REVIEW
10.3
Boiling vs. Evaporation
Boiling is The vaporization of a liquid at its boiling point.
Evaporation is
The vaporization of a liquid below its boiling point. This occurs at the surface of the liquid.
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Sublimation • Some substances go from the solid state directly
to the gaseous state. This happens when a substance was below it freezing point and is suddenly moved to a location where it is above its boiling point
• EX: CO2
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•It takes energy to cause phase changes( soild-liq-gas)
•Removal of energy (gas-liq-solid)
Phase changes do not change the substance
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• The amount of energy required for a substance to go from a solid to a liquid is
called the
HEAT OF FUSION. • (EX) it takes 334,000 Joules of energy to melt 1 kg of ice. No temperature change.
0°C 0°C
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• The amount of energy required to change a liquid to a gas is called the
…Heat of Vaporization
• EX: It takes 2,260,000
Joules of energy to
vaporize 1 kg of water.
100 °C 100 °C
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• The triple point
of a substance
is the temp. and
pressure at
which the three
phases of that
substance
coexist • Phase
depends
not only
on temp.
but also
pressure.
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Thermal Expansion •When objects are heated,
they expand. •When they are cooled, they
contract. • Video Clip
19 When heat is added to most materials they expand.
Thermometers •Work because of thermal expansion.
• Because mercury expands and contracts uniformly, it was used in
thermometers.
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• Pressure: The amt of force exerted per unit of area.
• Gases exert pressure by colliding with “things.” 1.Other particles of gas
2.Sides of the container
3.Objects within the area of the gas, like you.
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•Formula For Figuring Out Pressure:
•P = F/A
•The Pascal (Pa) is the SI unit of
pressure
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Clip
Boyle’s and Charles’ law
• Both deal with gases.
• Boyle’s Law
– As the volume
decreases, the
pressure increases.
• Charles’ Law
– As the temperature
decrease, the volume
of a gas decreases.
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Boyle’s Law • Relationship between volume
and pressure.
P1V1 = P2V2
You tube
Clip
Boyle’s Law A volume of helium occupies 11.0 L at 98.0 kPa. What is the new volume if the pressure
drops to 86.2 kPa?
P1 V1 = P2 V2 30
(V2)=12.5 L
(98.O kPa) (11.0 L) = (86.2 kPa) (V2)
P1 V1 = P2 V2
(98.O kPa) (11.0 L) = (V2)
(86.2 kPa)
• A sample of helium gas at 25°C is compressed from 200 cm3 to 0.240 cm3. Its pressure is now 3.00 cm Hg. What was the original pressure of the helium? – P1 = 3.60 x 10
-3 cm Hg
P1 V1 = P2 V2
Charles’ Law • Relationship between volume and
temperature.
In theory there is a temperature in which gases
ceases to have volume.
This temp. is referred to as absolute zero.
Absolute Temp. Scale T (K) = °C + 273.15 K
Charles’ Law 31
If you increase the temperature,
the volume will increase
Charles’ Law What would be the resulting volume of a 2.0 L balloon at 25.0˚C that was placed in a container
of ice water at 3.0˚C?
V1 = V2
T1 T2
2.0 L
25.0˚C
V2
3.0˚C =
V2 = 0.24 L
34.1
.
• Born: 287 BC in Syracuse, Sicily Died: 212 BC in Syracuse, Sicily
• “There are things
which seem
incredible to most
men who have not
studied mathematics.”
• “Eureka, Eureka. I have found [it].”
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• Despite his mathematical prowess, Archimedes is perhaps best remembered for an incident involving the crown of King Hiero.
• As the story goes, the king of Syracuse had given a craftsman a certain amount of gold to be made into an exquisite crown. When the project was completed, a rumor surfaced that the craftsman had substituted a quantity of silver for an equivalent amount of gold, thereby devaluing the crown and defrauding the king. Archimedes was tasked with determining if the crown was pure gold or not. The Roman architect Vitruvious relates the story:
• While Archimedes was considering the matter, he happened to go to the baths. When he went down into the bathing pool he observed that the amount of water which flowed outside the pool was equal to the amount of his body that was immersed. Since this fact indicated the method of explaining the case, he did not linger, but moved with delight, he leapt out of the pool, and going home naked, cried aloud that he had found exactly what he was seeking. For as he ran he shouted in Greek: Eureka! Eureka! (eureka translated is "I have found it").
• Although there is speculation as to the authenticity of this story, it remains famous. Probably no other tale in all of science combines the elements of brilliance and bareness quite so effectively. Whether the story is true or not, there is no doubt to the truth of Archimedes understanding of buoyancy.
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Here is what Archimedes had found. Since an object immersed in a fluid displaces the same volume of fluid as the volume of the object, it was possible to determine the precise volume of the crown by immersing it in water. After determining the volume of water, a piece of pure gold could easily be made to match the volume of the water, and thus the volume of the crown. In theory, if the volume of the crown and the volume of the gold block are the same, they should also have the same mass. The only reason they would not have the same mass is if one of them was not pure gold. When the two objects were placed in a balance they did not have equal mass. Faced with this evidence the craftsman confessed to his crime.
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• Why is it easier to lift something heavy when it's underwater?
•Buoyancy!
•Buoyancy is an upward force exerted by a fluid on an object that is submerged in that fluid.
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Eureka: Buoyancy
Archimedes’ Principle • Deals with fluids and buoyancy.
• What is a fluid?
• Any substance that can flow.
• Buoyancy is an upward force exerted by a fluid on on object that is submerged in that fluid.
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Archimedes’ Principle • Archimedes Principle states that the buoyant force on a submerged object is equal to the weight of the fluid that is displaced by the object.
•What does that mean? Describes how ships float. The more water you displace, the more upward force.
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Blaise Pascal
• Mathematician, physicist, and theologian.
• Pascal's work in the fields of the study of hydrodynamics and hydrostatics centered on the principles of hydraulic fluids.
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Pascal’s Principle •Pressure applied to a fluid is transmitted unchanged throughout the fluid.
•Toothpaste •Hydraulic Jacks
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Daniel Bernoulli
• Dutch-born mathematician.
• His most important work considered
the basic properties of fluid flow,
pressure, density and velocity, and
gave the Bernoulli principle.
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• As the velocity of a fluid increases, the pressure exerted by that fluid decreases.
• A plane's wing is curved so that the air going the greater distance over the top of the wing moves faster,
• Reducing pressure from above,allowing the lift from below to raise the plane up
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Amorphous Solids
• Lack highly ordered arrangement
• Melt over a temperature range
• Glass & Plastic
• Some scientist classify them as “thick liquids”
“without form”
Go Back to solids
•Amorphous solids are solids with random unoriented molecules
•Crystalline solids are arranged in fixed geometric patterns or lattices.