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States of Matter
Chapter 3Section 1 states of matter
Section 2 behavior of gasesSection 3 changes of state
3-1 STATES OF MATTER3-1 STATES OF MATTER
•The Four States of MatterThe Four States of Matter• Your textbook states that there are three states of Your textbook states that there are three states of
matter but you will be responsible for learning matter but you will be responsible for learning about four states of matter…I am throwing in the about four states of matter…I am throwing in the 5th state just so you can dazzle your high school 5th state just so you can dazzle your high school
science teacher!science teacher!SolidsSolids
LiquidsLiquids
GasesGases
PlasmaPlasma
STATES OF MATTERSTATES OF MATTER
Based upon particle arrangementBased upon energy of particlesBased upon distance between particles
Matter
• Matter is made of tiny particles.• Atoms - single element• Molecules -more than 1 type of element
• Atoms and molecules are always in a state of motion (much like the St. Ann students) and are always bumping into each other
STATES OF MATTERSOLIDS
•Particles of solids are tightly packed, vibrating about a fixed position.
•Solids have a definite shape and a definite volume. Heat
Solids
• Solids– Definite Shape– Definite Volume– Particles vibrate in fixed positions– Particles have low kinetic energy
Two Types of Solid Matter• Crystalline Solids
– Long-range order– Repeating patterns– Think back to the 6 different
crystalline structures you learned in the 6th grade
– Ex. Iron, diamond, ice
• Amorphous Solids– No long range order– Polymers, glass– Ex. Glass, rubber, wax
Sodium Chloride
STATES OF MATTERLIQUID
Particles of liquids are tightly packed, but are far enough apart to slide over one another.
Liquids have an indefinite shape and a definite volume. Heat
Liquids– Variable shape (takes the shape of the
container)– Definite Volume– Particles can move around each other– Particles have medium Kinetic Energy
Unique characteristics of liquids
• Surface tension- a force that acts on particles at the surface of a liquid – Remember the penny lab at the
beginning of the year– Water has a high surface tension so
forms droplets. Gas has a low surface tension and forms flat drops
• Viscosity- liquid’s resistance to flow– Higher the attraction between the
molecules, the more viscous the liquid
– Think about pouring water vs honey
STATES OF MATTERGAS
Particles of gases are very far apart and move freely.
Gases have an indefinite shape and an indefinite volume. Heat
Gases– Variable shape– Variable volume (fills all space in a container)– Particles move about freely– Particles have high Kinetic Energy
Classifying Matter According to its State:Solid, Liquid, Gas
• Water can exist as a solid, liquid or gas
But what happens if you raise the temperature to super-high levels…
between 1000°C and 1,000,000,000°C ?
Will everything just be a gas?
NO!If the gas is made up of particles which carry
an electric charge (“ionized particles”), but the entire gas as a whole has no electric charge, and if the density is not too high, then we can get
The 4th state of matter:
PLASMA
STATES OF MATTERPLASMA
A plasma is an ionized gas.
A plasma is a very good conductor of electricity and is affected by magnetic fields.
Plasmas, like gases have an indefinite shape and an indefinite volume.
• Plasma is the common state of matter
Some places where plasmas are found…
1. Flames
2. Lightning
3. Aurora (Northern Lights)
4. Neon lights
5. Stars
Stars make up 99% of the total matter in the Universe.
Therefore, 99% of everything that exists in the entire Universe is in the plasma state.
The Sun is an example of a star in its plasma state
6
6. Clouds of gas and dust around stars
STATES OF MATTER
SOLID LIQUID GAS PLASMA
Tightly packed, in a regular pattern
Vibrate, but do not move from place
to place
Close together with no regular arrangement.Vibrate, move
about, and slide past each other
Well separated with no regular arrangement.
Vibrate and move freely at high
speeds
Has no definite volume or shape and is composed
of electrical charged particles
But now what happens if you lower the temperature way, way, down to
100 nano degrees above
“Absolute Zero” (-273°C)
Will everything just be a
frozen solid?
Not Necessarily!In 1924 (82 years ago), two scientists, Albert
Einstein and Satyendra Bose predicted a 5th state of matter which would occur at very very low temperatures.
Einstein Bose
+
The 5th state of matter:
Bose-Einstein Condensate
Finally, in 1995 (only 12 years ago!), Wolfgang Ketterle and his team of graduate students discovered the 5th state of matter for the first time.
Ketterle and his students
This 5th state of matter will not be on any St. Ann test but you will dazzle your high school science teacher if you know that a 5th
state has been discovered!
To really understand Bose-Einstein
condensate you need to know
Quantum Physics
In 2002, Ketterle and two other scientists received the highest award in science for
discovering Bose-Einstein condensate:
The Nobel Prize
The five states of matter:
LIQUIDSSOLIDS GASES
Higher Temperature
Lower Temperature
PLASMAS(only for low density ionized gases)
BOSE-EINSTEIN
CONDENSATE
Kinetic Theory
• Kinetic energy = energy an object has due to its motion
• The faster an object is moving; the greater its kinetic energy.
• Kinetic theory states that all particles of matter are in constant motion.
Classifying Matter According to its State:Kinetic Theory
3-2 Behavior of Gases
The three main states of matter that we meet daily are: gas, liquid, and solid. Gases can be compressed, they expand to fill their containers. The volume of a gas is variable
In this room right now are millions of gas molecules and atoms colliding with the walls, the floor, your face and each other.
Can you feel it?
One property of gases is that they exert pressure.
The pressure exerted by the gas mixture we call air is called atmospheric pressure. The atmosphere that surrounds Earth is a sea of air. It exerts a force on the surface of the planet.
Above you is a column of air that is exerting a force on you.
This pressure can be measured.
But why is air exerting pressure?
Pressure
• Pressure = the result of force distributed over an area
• In a closed container, gases exert pressure when the particles of the gas collide with the walls of the container.
Compressibility• Solids are incompressible• Gases are compressible• Liquids are very slightly
compressible – usually considered incompressible
Factors That Affect Gas Pressure
• Temperature – raising temp. will increase pressure if volume of gas and # of particles are kept constant
– Inc. in temp. part. move faster part. collide with walls more frequently increased pressure
• Volume – Decreasing volume of a gas causes an increase in pressure if the temp. and # of part. are constant
– Decrease in vol. less space particles collide with walls more often inc. pressure
• Number of particles – increasing the number of particles of a gas will increase pressure if temp. and volume are constant
– Inc. # of particles particles collide with container more often inc. pressure
Why is air pressure important?It causes wind
Creates clouds and clear skiesAllows us to predict the weather
Pressure and Volume Boyles Law
The volume of a gas is inversely proportional to its pressure
P1V1 = P2V2
Irish scientist Robert Boyle experimented with the relationship between pressure and volume of gases.
He set-up a J-shaped tube and added mercury to see what it did to the volume of a trapped gas.
As pressure increased volume decreases.
Pressure and Volume Boyles Law
If the volume is increased the gas particles collide with the walls of the container less often and the
pressure is reduced.
Boyle’s Law
Boyle’s Law (temp constant)
• A decrease in the volume of gas will result in an increase in pressure
• An increase in the volume of gas will result in a decrease in pressure
V1P1 = V2P2
French physicist Jacques Charles was the first to fill a balloon with hydrogen gas and make a solo flight.
He showed that the volume of a gas increases when the temperature increases (at a constant pressure)
Volume and Temperature Charles’s Law
The volume of a gas is directly proportional to its Kelvin temperature at constant pressure
V1
T1
V2
T2
=
Charles’ Law
Charles’s Lawpressure constant
Volume of a gas increases with increasing temperature
Volume of a gas decreases with decreasing temperature
V1 = V2T1 T2
Principle- Use
Boyles (temperature constant)Squeezing a balloon
Charles (pressure constant)Why balloons decrease in size when kept in a cold room
Reason for statement on hair spray: “keep away from heat, contents under pressure”
Websites for additional help
• http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/gasesv6.swf
• http://www.grc.nasa.gov/WWW/K-12/airplane/aboyle.html
• http://www.virtlab.com/main.aspx
3-3 Changes of State
• What would it take for matter to move from one state to another?
Melting and Freezing
• Melting– Solid changes to liquid– Particles absorb energy (endothermic)– Particles become less orderly
• Freezing– Liquid changes to solid– Particles release energy (exothermic)– Particles become more orderly
Vaporization and Condensation
• Vaporization– Liquid changes into a gas– Particles absorb energy (endothermic)– Particles become LESS orderly and more free
to move– 2 types of vaporization
• Evaporation – takes place at the surface of a liquid• Boiling – occurs when a liquid is heated to its
boiling point
• Condensation– Gas changes to a liquid– Particles release or lose energy (exothermic)– Particles become MORE orderly
Sublimation and Deposition
• Sublimation– Changing from a solid
directly to a gas– Energy is absorbed
(endothermic)
• Deposition– Changing from a gas directly to a solid– Energy is released (exothermic)
PHASE CHANGESDescription of Phase Change
Term for Phase Change
Heat Movement DuringPhase Change
Solid to liquid
MeltingHeat goes into the solid as it melts.
Liquid to solid
FreezingHeat leaves the liquid as it freezes.
PHASE CHANGESDescription of Phase Change
Term for Phase Change
Heat Movement During Phase Change
Liquid to gas
Vaporization, which includes boiling and evaporation
Heat goes into the liquid as it vaporizes.
Gas to liquid
CondensationHeat leaves the gas as it condenses.
Solid to gas SublimationHeat goes into the solid as it sublimates.
Phase Changes• Melting
– Going from Solid to Liquid• Freezing
– Going from Liquid to Solid• Vaporization
– Going from Liquid to Gas• Condensation
– Going from Gas to Liquid• Sublimation
– Going from Solid to Gas
Phase Change Diagram