states of matter a kinetic experience. what is a solid? solids have a definite shape and definite...
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States of Matter
A Kinetic Experience
What is a solid?
• Solids have a definite shape and definite volume.
• Molecules are tightly packed and vibrate. They stay fairly still.Crystalline Solids- Repeating pattern ex. Ghost crystals, crystals in rocks, salt, rock candyAmorphous Solids- - Non-repeating pattern ex. Wax, play dough, hand putty, peanut butter, gum, clay
What is a liquid?• Liquids have no definite shape, but a
definite volume. • Molecules are closely packed but can
vibrate and slide around one another.• A misconception that molecules do not
touch in a liquid.Examples: Water in different sized containers.Water in syringeWater in baggie.
DRAW A LIQUID.
Solid/LiquidCheck-Up
1. Describe particle motion in a solid.2. Describe particle motion in a liquid.3. What are two different types of
solids? Give 1 example of each.4. What is a common misconception
about liquids?
What is a Gas?• Gases have no definite shape and no definite
volume.• Molecules can vibrate, slide, spin, and bounce
off of one another.• Gases diffuse (The movement of particles from a
region of high concentration to a region of low concentration) .
• Heat will increase the rate of diffusion. Examples:
Perfume, Lysol, “tooting your little horn”
What is plasma?• Plasma is ionized gas (an atom with a
charge)• This is an extreme gas! Strikes the other
atoms so forcefully it knocks off an electron!
• These gases vibrate, slamming into one another causing bright gases, lots of heat and lots of energy.Examples:Our Sun, Plasma TV, plasma cutters, neon signs, and plasma balls
DRAW PLASMA.
Gas/Plasma Check-Up
1. Describe particle motion in a gas.2. Describe particle motion in plasma.3. What is another name for plasma?4. How is plasma formed?
Balls in Box Demo
• Small vibrations = Solid• More Energy Added in the form of
heat energy, bouncing inside box = Liquid
• Even More Energy Added in the form of heat energy, balls falling out of box = Gas (evaporation) Heavier molecules evaporate at a slower rate.
• Putting the balls back into the box = Condensation
Why metal balls inside some of the tennis balls?
• Heavier molecules take more energy to evaporate.
• Lighter molecules evaporate more readily.
Kinetic Theory of Matter
• All matter is made of molecules and atoms that act like tiny particles
• Molecules are always in motion. The higher the temperature, the faster the particles move
• At the same temperature, heavier particles move slower than lighter particles.
Molecular Theory of Matter• Also known as the Kinetic theory of matter:
• States that everything is made up of particles known as molecules, and that these particles are constantly moving.
• If the motion is fixed around a point in space, its a solid,
• if the molecules can freely move around and between each other, its a liquid,
• and if the molecules can move independently from each other, its a gas.
Phase Changes
• Draw the diagram that is on the right hand side of the board.
• You will need to have this memorized.
Evaporation
Matter changing from a liquid to a gas.
Matter changes because energy is added to the system.
Evaporation DemonstrationsAlcohol Timing- Alcohol evaporated quicker than water because molecules
are lighter.Butane in Baggie- Butane’s boiling point is so low that the heat from your
body will make butane reach it’s boiling point.Super Heated Steam- Water molecules move so fast that are able to burn paper.Flaming Flask- Mystery substance is less dense than water and burns
until all molecules are evaporated.Flaming Money – Alcohol is evaporated when heat energy is added. Money
is dry.
Review Questions
1. How does temperature effect state change?
2. Why does alcohol evaporate quicker than water?
3. When butane changes from a liquid to a gas is energy released or absorbed?
4. Why did the flaming money remain unharmed when it was caught on fire?
Sublimation
Matter changing from a solid directly to a gas. (skipping the liquid phase)
Examples:Dry Ice (frozen Carbon Dioxide)Snow in parking lot that does not meltMothballs in closetOld ice cubes in freezer
Condensation
• Matter changing from a gas to a liquid.
Examples:Glass of ice waterBathroom mirror after showerHot breath on bus windowDew on grass.
Deposition
• Matter changing from a gas directly to a solid. (Skipping the liquid phase)
Examples:Frost on glassDemo – Mothballs on a hotplate making crystals.
Thermal Expansion• Thermal expansion is the tendency of a matter to
change in volume in response to a change in temperature.
Examples:Demo - Ball and RingDemo- Bimetallic Strip (Brass and Iron)Sidewalk crackingDoorwayCracks in house foundationDemo – Drinking BirdDemo – Hand Boiler
