STATES OF MATTER & PHASE CHANGES

Solid

(a) Particles in solid (b) Particles in liquid (c) Particles in gas

Liquid Gas

States of Matter

Solid Liquid Gas

Holds Shape

Fixed Volume

Shape of Container

Fixed Volume

Shape of Container

Volume of Container

heat heat

States of Matter

Solid Liquid Gasheat heat

States of Matter

State Particle Model

Shape Volume Energy

Solid Definite Definite lowest

Liquid Indefinite Definite

Gas Indefinite Indefinite highest

Characteristics of Solids

Particles are very tightly packed

Definite shape, definite volume

Particles vibrate but cannot move

Characteristics of Liquids

Looser attraction between particles

indefinite shape, definite volume

Particles can tumble over each other

Liquids can flow

Characteristics of Gases

No attraction between particles

indefinite shape, indefinite volume

Particles move rapidly and are in constant motion

Gases can flow

What is the state of oobleck?

Discuss with your group which state of matter oobleck should be classified as.

Cite evidence for your answer!

http://www.youtube.com/watch?v=yHlAcASsf6U

Phase Changes

Melting

Freezing

Vaporization

Condensation

Deposition

Sublimation

Can you comeup with an example

for each?

Phase Changes

Let’s Label Together!

Phase Changes

Answer:

Food for Thought

There is a 4th state of matter known as plasma. A plasma is an ionized gas A plasma is a very good conductor of electricity

and is affected by magnetic fields.

Examples:

Phase Diagram of Water

Defining a Phase Diagram

A phase diagram is common way to represent the various phases of a substance and the conditions under which each phase exists

solid

liquid

gas

vaporization

condensation

melting

freezing

Heat added

Tem

pera

ture

(oC

)

A

B

C

DE

Heating Curve for Water

0

100

LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 487

What does this phase diagramtell you?

Interpreting a Phase Diagram 6. What is the melting

point of the substance?

7. What is the boiling point of the substance?

8. What letter on the diagram indicates solid is present only?

A

B

C

D

About 55°C

About 95°C

A

Interpreting a Phase Diagram 9. What letter on the

diagram indicates a gas is present only?

10. What letter on the diagram indicates a liquid is present only?

11. What letter on the diagram indicates both solid AND liquid are present?

A

B

C

D

B

C

D

Questions about Phase Change Lab?

Analysis Questions

Claims and Evidence

Reflection Questions

LAB REPORT DUE THURSDAY, APRIL 4th.

Types of Reactions

Endothermic reaction- Energy is gained by the substance as it changes state Heat is needed/absorbed.

Exothermic reaction-Energy is removed by the substance as it changes state. Heat is released.

Discuss with your partner:What phase changes are endothermic?

EXOTHERMIC?

Phase Changes - Melting

Melting is when a substance changes from a solid to a liquid.

Do particles gain or lose speed?

The particles increase their speed causing them to break apart from each other.

Endothermic or Exothermic Reaction? Endothermic

Examples-melting snow or ice

Phase Change – Condensing Condensing is when a substance changes

from a gas to a liquid.

Do particles gain or lose speed? The particles lose their speed causing them to

pack a little more closely together.

Endothermic or Exothermic Reaction? Exothermic Reaction

Example: Cloudy bathroom

Let’s Change some Phases by…

MAKING ICE CREAM!

Take a Look at Your Lab

CHANGE PROCEDURE #5 TO SAY ½ CUP OF ROCK SALT

solid

liquid

gas

vaporization

condensation

melting

freezing

Heat added

Tem

pera

ture

(oC

)

A

B

C

DE

Heating Curve for Water

0

100

LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 487