States of Matter

Ms Rochford

First Year Science

In this topic:

• Properties of solids, liquids and gases

• Using a Bunsen burner

• Changing states:

– Melting

– Condensation

– Evaporation

• Diffusion

States of Matter

• Matter: anything that occupies space and has mass

• 3 main states:

1. Solid

2. Liquid

3. Gas

Properties of the states

• What do I mean by “Properties”?

• The qualities that make an object

what it is

– What it looks like

– What it is made of

– What it feels like

– What it can do

– ……..

What are they made of?

• All matter is made up of tiny particles

• Known as ATOMS

• Groups of atoms join to form MOLECULES

• Would need a really really powerful microscope to see them

Solids

• Molecules packed closely together

• Lattice structure

• Doesn’t flow

• Can’t be compressed

• Strong structure

Investigating properties of Solids

• Can you compress it

or make it smaller?

• Can you pour it or

make it flow?

Liquids

• Weaker bonds between molecules

• More freedom to move & slide

• Flows

• Take shape of what they are put

into

• Can’t be compressed

Investigating properties of Liquids • Does the water flow?

• Does it change shape?

• Does it change

volume?

• Can we compress it?

Gas • Very weak bonds between

molecules

• Complete freedom to move

• Move very fast

• Flows

• Moves to fill space

• Can be compressed

Investigating properties of gases • Does the gas flow?

• Does it change

shape?

• Can we compress

it?

Summary

SOLID LIQUID GAS

Definite shape No definite shape

No definite shape

Definite volume Definite volume No definite volume

Can’t be compressed

Can’t be compressed

Can be compressed

Cannot flow Can flow Can flow

Bunsen Burner

How to light a bunsen burner

1. Put on safety glasses and tie back hair

2. Plug into gas supply

3. Make sure the air hole is fully closed

4. Light match

5. Partner turn on gas

6. Pass lighter or match slowly over top of bunsen burner

Bunsen Burner

3 different flames:

1. Yellow safety flame

2. Quiet blue

3. Loud blue

Safety first…..

• No faces or arms near top of bunsen burner

• Leave on yellow “safety flame” when not in use

• Use tongs and test tube holders for hot equipment

• Don’t heat an empty glass object

Bunsen Burner: hottest part of flame

Matter can change states

• We know that water can be:

– solid (ICE),

– liquid (WATER) and

– gas (STEAM)

Melting

Melting: the changing of a solid to a liquid

Melting point: the temperature when a solid turns into a liquid

Melting point

• Melting point of water = 0 °C

• Melting point of alcohol = -114 °C

Evaporation

• Can be through boiling

• Or from heat from the sun

Evaporation: the changing of a liquid to a gas

Boiling

Boiling point: the temperature at which a liquid turns into a gas through the liquid

• Boiling point of water = 100 °C

• Boiling point of alcohol = 78.5 °C

Condensation

Condensation: the changing of a gas into a liquid

Freezing or solidification

• Freezing point of water: 0 °C

• Freezing point of alcohol: -114.6 °C

Freezing/solidifying: the changing of a liquid to a solid

Activity 2: Changes of state

Activity 2: Part 1

Continue heating until it bubbles

1. What happens to the ice?

2. What do we call this?

3. What does the water turn into?

4. What is the name of this change?

• Hold a dry test tube above the beaker

• Observe for about 20 seconds

5. What has formed on the test tube?

6. What do we call this change?

Part 2

• Keep hot water • DO NOT LET BOIL DRY • Place a test tube with

some wax into the hot water

7. What change occurs? 8. To what state does it

change?

• Turn off bunsen burner

• Use test tube holder

• Place hot test tube into the test tube rack

• Leave for a while

9. What does it change to?

Summary of changes of state

Changing states

MELTING Solid Liquid 1.

Liquid Gas 2. EVAPORATION

Gas Liquid 3. CONDENSATION

Liquid Solid 4. FREEZING /

SOLIDIFICATION

Diffusion

• Where is the smell coming from & how does it spread?

What is Diffusion?

• Move from areas of high concentration to areas of low concentration

Diffusion: the way in which particles in gases and liquids spread out

Can you explain why….

1. Diffusion occurs both in liquids and gases but hardly at all in solids?

2. Diffusion happens more quickly for gases than for liquids.

Chapter 17: Solids, Liquids and Gases

DONE!!