Chapter 3 – States of Chapter 3 – States of MatterMatter

3.1 Solids, Liquids, and 3.1 Solids, Liquids, and GasesGases

SolidsSolids– Definite ShapeDefinite Shape– Definite VolumeDefinite Volume– Particles vibrate in fixed positionsParticles vibrate in fixed positions– Particles have low kinetic energyParticles have low kinetic energy

LiquidsLiquids– Variable shape (takes the shape of the Variable shape (takes the shape of the

container)container)– Definite VolumeDefinite Volume– Particles can move around each otherParticles can move around each other– Particles have medium Kinetic EnergyParticles have medium Kinetic Energy

GasesGases– Variable shapeVariable shape– Variable volume (fills all space in a Variable volume (fills all space in a

container)container)– Particles move about freelyParticles move about freely– Particles have high Kinetic EnergyParticles have high Kinetic Energy

PlasmaPlasma– Exists only at extremely high Exists only at extremely high

temperaturestemperatures– 99% of the matter in the UNIVERSE is 99% of the matter in the UNIVERSE is

plasmaplasma– Stars are plasmaStars are plasma

Einstein-Bose CondensateEinstein-Bose Condensate– Exists only at extremely low Exists only at extremely low

temperaturestemperatures– Groups of atoms behave as a single Groups of atoms behave as a single

particleparticle

Kinetic TheoryKinetic Theory

Kinetic energy = energy an object Kinetic energy = energy an object has due to its motionhas due to its motion

The faster an object is moving; the The faster an object is moving; the greater its kinetic energy.greater its kinetic energy.

Kinetic theory states that all particles Kinetic theory states that all particles of matter are in constant motion.of matter are in constant motion.

** View animation on visual concepts CD** View animation on visual concepts CD

3.2 The Gas Laws3.2 The Gas Laws

Pressure = the result of force Pressure = the result of force distributed over an areadistributed over an area– More Collisions=More PressureMore Collisions=More Pressure

In a closed container, gases exert In a closed container, gases exert pressure when the particles of the pressure when the particles of the gas collide with the walls of the gas collide with the walls of the container.container.

Factors That Affect Gas Factors That Affect Gas PressurePressure

Temperature – raising temp. will Temperature – raising temp. will increase pressure if volume of gas and increase pressure if volume of gas and # of particles are kept constant# of particles are kept constant

– Inc. in temp. Inc. in temp. part. move faster part. move faster part. part. collide with walls more frequently collide with walls more frequently increased pressureincreased pressure

Volume – Decreasing volume of a gas Volume – Decreasing volume of a gas causes an increase in pressure if the causes an increase in pressure if the temp. and # of part. are constanttemp. and # of part. are constant

– Decrease in vol. Decrease in vol. less space less space particles collide with walls more often particles collide with walls more often inc. pressureinc. pressure

Number of particles – increasing the Number of particles – increasing the number of particles of a gas will number of particles of a gas will increase pressure if temp. and increase pressure if temp. and volume are constantvolume are constant

– Inc. # of particles Inc. # of particles particles collide particles collide with container more often with container more often inc. inc. pressurepressure

Gas LawsGas Laws

Charles’ Law – volume of a gas is Charles’ Law – volume of a gas is DIRECTLY PROPORTIONAL to DIRECTLY PROPORTIONAL to temperaturetemperature– Inc. Temp. x2 Inc. Temp. x2 Inc. Vol. x2 Inc. Vol. x2

VV11 = = VV22

TT11 T T22

Boyle’s Law – volume of a gas is Boyle’s Law – volume of a gas is INVERSELY PROPORTIONAL to INVERSELY PROPORTIONAL to pressurepressure– Inc. Vol. x2 Inc. Vol. x2 Dec. pressure by Dec. pressure by

½½

PP11VV11 = P = P22VV22

Combined Gas LawCombined Gas Law

The Combined Gas Law – relates The Combined Gas Law – relates temperature, volume and pressure temperature, volume and pressure of a gas.of a gas.

Formula:Formula:PP11VV11 = = PP22VV22

TT11 T T22

3.3 Phase Changes3.3 Phase Changes

Phase change – reversible physical Phase change – reversible physical change that occurs when a change that occurs when a substance changes from one state substance changes from one state of matter to anotherof matter to another– Temperature of a substance DOES NOT Temperature of a substance DOES NOT

CHANGE during a phase change.CHANGE during a phase change.– Energy is either absorbed or released Energy is either absorbed or released

during a phase change.during a phase change. Endothermic – energy is absorbedEndothermic – energy is absorbed Exothermic – energy is releasedExothermic – energy is released

Melting and FreezingMelting and Freezing

MeltingMelting– Solid changes to liquidSolid changes to liquid– Particles absorb energy (endothermic)Particles absorb energy (endothermic)– Particles become less orderlyParticles become less orderly

FreezingFreezing– Liquid changes to solidLiquid changes to solid– Particles release energy (exothermic)Particles release energy (exothermic)– Particles become more orderlyParticles become more orderly

Vaporization and Vaporization and CondensationCondensation

VaporizationVaporization– Liquid changes into a gasLiquid changes into a gas– Particles absorb energy (endothermic)Particles absorb energy (endothermic)– Particles become LESS orderly and more Particles become LESS orderly and more

free to movefree to move– 2 types of vaporization2 types of vaporization

Evaporation – takes place at the surface of a Evaporation – takes place at the surface of a liquidliquid

Boiling – occurs when a liquid is heated to its Boiling – occurs when a liquid is heated to its boiling pointboiling point

CondensationCondensation– Gas changes to a liquidGas changes to a liquid– Particles release or lose energy Particles release or lose energy

(exothermic)(exothermic)– Particles become MORE orderlyParticles become MORE orderly

Sublimation and Sublimation and DepositionDeposition

SublimationSublimation– Changing from a solid Changing from a solid

directly to a gasdirectly to a gas– Energy is absorbedEnergy is absorbed

(endothermic)(endothermic) DepositionDeposition

– Changing from a gas directly to a solidChanging from a gas directly to a solid– Energy is released (exothermic)Energy is released (exothermic)

Phase Change DiagramPhase Change Diagram