Properties of MatterProperties of MatterChapter 2 – Physical Science

Kinetic TheoryKinetic Theory

All matter is made of atoms and molecules that act like tiny particles

These particles are always in motion. The higher the temperature, the faster they move

At the same temp., more massive particles move slower than less massive particles

States of MatterStates of Matter

Solid = definite volume, definite shape

Liquid = definite volume, no definite shape

Gas = no definite volume, no definite shape

Plasma = gas-like, no definiteshape or volume

SolidsSolids

Have a rigid structure

Particles have almost no freedom to change position, low KE

Still vibrate around a fixed location

LiquidsLiquids

Take the shape of their container

Particles are held close together, but not attracted as strongly as particles in a solid, higher KE

Classified as a fluid because it can flow

GasesGases

Free to spread in all directions

Under standard conditions, gas particles move rapidly, high KE

Exert pressure, but can be compressed into a smaller volume

PlasmaPlasma

very high KE - particles collide with enough energy to break into charged particles (+/-)

gas-like, no definiteshape or volume

stars, fluorescentlight bulbs, TV tubes

Thermal ExpansionThermal Expansion

Most matter expands when heated & contracts when cooled

Temp causes KE - Particles collide with more force & spread out

Examples: Sidewalk dividersThermometers

Changes of StateChanges of State

Changing states of matter requires energy

Changes of StateChanges of State

Evaporation =

Condensation =

Melting =

Freezing =

Sublimation =

Liquid -> Gas

Gas -> Liquid

Solid -> Liquid

Liquid -> Solid

Solid -> Gas

ConservationConservation

Law of Conservation of MassMass cannot be created or destroyedMass of reactants = mass of products

Law of Conservation of EnergyEnergy cannot be created or destroyedEnergy is converted from one form to

another

Part 2Part 2

Looking at matter and observing its qualities

Physical PropertiesPhysical Properties

Properties that do not change the chemical nature of matter

Examples: color, smell, freezing point, boiling point, melting point, magnetic attraction or repulsion, texture, volume, mass, weight, viscosity and density

Physical PropertiesPhysical Properties

List some physical properties:

Chemical PropertiesChemical Properties

Properties that do change the chemical nature of matter

Examples are: flammability, reactivity with water, pH, types of bonds

Physical ChangesPhysical Changes

A change in the physical form or properties of a substance that occurs without a change in composition

Examples: change in state, dissolving, breaking, changing shape

Can usually be reversed

Physical ChangesPhysical Changes

Name the physical change occurring:

Melting

Condensation

Boiling

Physical ChangesPhysical Changes

Evaporation

Physical ChangesPhysical Changes

Sublimation

Chemical ChangesChemical Changes

A change that occurs when a substance changes composition by forming one or more new substances

Examples: burning, rusting, cookingHints: heat or light may be given off,

smell or color change

What Type of Change?What Type of Change?