•A Small Rock•100 ml of Water•The Helium from a

Balloon

Which is easiest to

hold in your hand? Why?

State (or phase) of Matter

• The physical form in which matter exists

• Four states– Solid– Liquid Most common on Earth– Gas– Plasma

SOLIDS• Have a definite shape and

volume– How do we find the volume of a

solid?•Length x Width x Height

Liquids•Has a definite volume.

– How do we find a liquid’s volume?

•What is a liquid’s shape?– It takes the shape of its’

container– No definite shape

Gases• No definite shape or volume

– Takes the shape of its’ container– Gas molecules will spread out to

occupy all of the space available.

PLASMA• Forms when temperatures are high enough to remove electrons from their atoms– When an atom loses electrons, it becomes a positively charged ion.

Particles and Phase

•The arrangement and motion of the particle that make up a substance determine its state.

SOLIDS• Particles are packed

together quite closely• The energy bonding

these particles is very strong– This prevents particles

from moving freely

• Particles move by vibrating in their position– Gives solids their

definite shape and volume

Liquids• Particles are less

densly packed than those in a solid

• Energy bonding particles is weaker than in a solid– Particles can move

around and slide past one another

• Movement of particles prevents liquids from having a definite shape

Gases• Particles move

freely– Allows gases to

expend and contract to fit its container• Thus gases lack

shape and volume

• Energy binding the particles is weak

Heat Affects the State of a Substance

• When a substance takes in heat, its particles gain energy and move more quickly

• When a substance releases heat, its particles lose energy and move more slowly.

When enough heat is added or removed, a change of state

occurs.

• Solid + Heat =

• Liquid + Heat =

• Gas – Heat =

• Liquid – Heat =

LIQUID

GAS

LIQUID

SOLID

Solid + Heat = Liquid

–Melting point: the temperature at which a solid begins to change to a liquid.

Liquid + Heat = Gas

• Vaporization– The process in which a liquid changes to a gas

• Boiling Point– The temperature at which a liquid changes to a gas

Gas – Heat = Liquid

• Condensation– The changing of a substance from a

gas to a liquid– The temperature is the same as the

substance’s boiling point, it’s just going in the opposite direction.

Check it Out!

http://www.harcourtschool.com/activity/states_of_matter/molecules.swf

Phase Change Diagram

Freezing

Condensing

Boi

ling

Melti

ng

HEAT ENERGY

TEM

PER

ATU

RE