Energy Energy

The ability to do work or make The ability to do work or make change.change.

TemperatureTemperature

Is the Is the measure measure of the averageof the average

kinetic energy of particles of matter.kinetic energy of particles of matter.• We measure temperature in We measure temperature in Celsius (˚c)Celsius (˚c)

Freezing point of water- Freezing point of water- 0˚c0˚c Boiling point of water- Boiling point of water- 100˚c100˚c

• Kinetic Energy- is the energy of motion.Kinetic Energy- is the energy of motion. It is the motion of waves, electrons, atoms, It is the motion of waves, electrons, atoms,

molecules, substances, and objects.molecules, substances, and objects.

Thermal EnergyThermal Energy

Thermal energy is the Thermal energy is the internalinternal energy in substances.energy in substances.• Also known as heat or radiant energy.Also known as heat or radiant energy.• It is the vibration and movement of the It is the vibration and movement of the

atoms and molecules within substances.atoms and molecules within substances.• The more thermal energy in a The more thermal energy in a

substance, the faster the atoms and substance, the faster the atoms and molecules vibrate and move.molecules vibrate and move.

Four StatesFour States of Matter of MatterThe physical forms in which a

substance can exist

•SolidSolid•Liquid Liquid •GasGas •PlasmaPlasma

Solid StateSolid State

Solids have a Solids have a definitedefinite shape and volumeshape and volume

• Particles of the substance Particles of the substance are very close togetherare very close together

• Two types of solids:Two types of solids: Crystalline Crystalline AmorphousAmorphous

Crystalline SolidsCrystalline Solids

Crystalline solids have a very orderly, Crystalline solids have a very orderly, three-dimensional arrangement of three-dimensional arrangement of atoms or molecules. Particles repeat atoms or molecules. Particles repeat in in patternspatterns or rows or rows

Example: Example: diamonds, salt ,sugardiamonds, salt ,sugar

Amorphous SolidsAmorphous Solids

Amorphous solid are arranged Amorphous solid are arranged randomly.randomly.

Each particle is in a particular spot, Each particle is in a particular spot, butbut the particles are in the particles are in no particular no particular pattern.pattern.

Example: Example: tires, rubber, waxtires, rubber, wax

LiquidsLiquids

Do not have a definite Do not have a definite shape but do have a shape but do have a definite volume.definite volume.• Liquids take the shape of Liquids take the shape of

their their containercontainer..• Molecules in liquid move Molecules in liquid move

fast by each other, and are fast by each other, and are close to each otherclose to each other

Liquid PropertiesLiquid Properties

Surface Tension Surface Tension is the result of an inward pull is the result of an inward pull among molecules that beings the molecules among molecules that beings the molecules on the surface closer together.on the surface closer together. Ex: Ex: beads of water on a car or leaf, bugs walking on beads of water on a car or leaf, bugs walking on

water.water.

ViscosityViscosity a liquids resistance to flowing. a liquids resistance to flowing.• Depends on Depends on size, shape, and attraction of particles.size, shape, and attraction of particles.

Gas StateGas State Do not have a definite

shape or volume

• In a gas there are empty spaces between particles.

• Gas molecules- move fast enough to break

away from each other. have less attraction between

them.

PlasmaPlasma

Plasma is a Plasma is a gas like state of matter gas like state of matter consisting of a consisting of a mixture of free electrons and atoms that are stripped mixture of free electrons and atoms that are stripped of their electrons (ionized). of their electrons (ionized).

Where is Plasma? Both ordinary and exotic places!Where is Plasma? Both ordinary and exotic places!• When an electric current is passed through neon gas, it When an electric current is passed through neon gas, it

produces both plasma and light. Also in fluorescent produces both plasma and light. Also in fluorescent lights.lights.

• Lightning is a massive electrical discharge in the Lightning is a massive electrical discharge in the atmosphere that creates a jagged column of plasma.atmosphere that creates a jagged column of plasma.

• Part of a comet's streaming tail is plasma from gas Part of a comet's streaming tail is plasma from gas ionized by sunlight and other unknown processes. ionized by sunlight and other unknown processes.

• The Sun is a 1.5-million-kilometer ball of plasma, The Sun is a 1.5-million-kilometer ball of plasma, heated by nuclear fusion heated by nuclear fusion

Phase ChangePhase Change A phase change occurs when matter A phase change occurs when matter

changes from one state to another. changes from one state to another. This is a This is a physicalphysical change. change.

Vaporization/condensation

Sublimation

Melting/ freezing

Thermal Changes in MatterThermal Changes in Matter

Endothermic ChangeEndothermic Change, a change in , a change in which energy is taken which energy is taken inin..• Example: The melting of ice, Ice packsExample: The melting of ice, Ice packs

Exothermic ChangeExothermic Change, a change in , a change in which energy is which energy is released.released.• Example: A burning fire, Calcium Example: A burning fire, Calcium

Chloride & HChloride & H22OO

MeltingMelting Is the change of state from a solid Is the change of state from a solid

to a to a liquidliquid.. The melting point of a substance is The melting point of a substance is

the point at which the substance the point at which the substance changes changes from a solid to a liquid.from a solid to a liquid.

Melting pts. of substances vary.Melting pts. of substances vary. Melting pts. can be used to Melting pts. can be used to

identifyidentify a substance, it is a a substance, it is a property of matterproperty of matter

Melting is a Melting is a endothermicendothermic change change• Heat energy is absorbed, or taken in.Heat energy is absorbed, or taken in.

FreezingFreezing Freezing is the change of Freezing is the change of

state from a state from a liquid to a liquid to a solidsolid..

Freezing is the reverse Freezing is the reverse process of melting. SO, process of melting. SO, freezing and melting occur freezing and melting occur at the same temperature.at the same temperature.

Freezing is Freezing is exothermicexothermic change . change . • Heat energy is removed or Heat energy is removed or

taken out.taken out.

VaporizationVaporization Is a change from liquid to Is a change from liquid to

gasgas Boiling is vaporization that Boiling is vaporization that

occurs occurs throughoutthroughout the liquid. the liquid.• Boiling pt. is a physical Boiling pt. is a physical

property of matterproperty of matter• When a liquids becomes a gas When a liquids becomes a gas

the atoms spread apart.the atoms spread apart.• Pressure affects boiling pointsPressure affects boiling points

Evaporation is vaporization Evaporation is vaporization that occurs at the that occurs at the surfacesurface of of the liquid. the liquid.

- Evaporation point - Evaporation point is below boiling pt.is below boiling pt.

CondensationCondensation

Condensation is the change of state Condensation is the change of state from a from a gas to a liquidgas to a liquid..

Condensation Point: The temperature Condensation Point: The temperature at which the gas becomes a liquid at at which the gas becomes a liquid at a given pressure.a given pressure.

When a gas becomes a liquid atom When a gas becomes a liquid atom clump together. clump together.

Condensation is Exothermic Condensation is Exothermic

SublimationSublimation

Is a change from a solid state Is a change from a solid state directlydirectly to a gas state. to a gas state. • Ex: Dry IceEx: Dry Ice