Chapter 17 Solids, Liquids & Gases

Objectives1. To introduce the term Matter as a word used to describe materials.

2. To carry out experiments to show that gas occupies space and has mass.

3. To discuss the properties of the three states of matter solid, liquid and gas

4. To investigate changes in state from solid, liquid to gas and look at water as an example

5. To define a number of terms including melting point, boiling point, evaporation and condensation

Matter is anything which occupies space and which as mass

Solids Liquids Gases

Example: Example: Example:

Use the following vocabulary

Definite shape (does not flow) definite volume, hard to compressEasy to compress, no definite volume, No definite shape

Solids Liquids Gases

Example: gold Example: water Example: oxygen

Definite Shape No definite shape No definite shape

Definite Volume Definite Volume No definite volume

Cannot flow Can flow Can flow

Cannot be compressed Cannot be compressed Can be compressed

States of Matter: Properties

Title: States of MatterAim: To show that a gas occupies space

Apparatus: Gas jar, beehive shelf, glass trough, straw

Safety: (2 points)

Method:

1. Set up apparatus as shown in diagram

2. Blow gently into the water as shown in the diagram

3. Observe what happens inside the gas jar.

Result:

As you blow into the gas jar full of water the gas takes up space and forces the water out. The level of water in the gas jar falls.

Conclusion: A gas occupies space

Diagram:

Title: States of Matter Date: Aim: To show that a gas has mass

Apparatus: Electronic balance, 2 balloons, safety glasses,

Safety: (2 points)

Method:

1. Place a deflated balloon on a balance an find its mass.

2. Inflate the balloon by blowing into it. Place the inflated balloon on the balance and record its mass.

Mass of deflated balloon

g

Mass of Inflated balloon

g

Mass of air in balloon

g

Results Table

Result: The balloon filled with air has a greater mass than the empty balloon.

Diagram:

Conclusion: Air has mass.

Quiz

How many states of matter are there?

Can you name the states of matter?

Summary of Properties of the States of Matter

Solids Liquids Gases

Definite shape (do not flow)

No definite shape (flow easily)

No definite shape (diffuse to fill up all available space)

Definite volume Definite volume No definite volume

Hard to compress Hard to compress Easy to compress

Changes of StateWhen solids are heated their particles gain energy and move apart.

The particles then break free from their positions and the solid melts to form a liquid

Particle Theory

Solids1. Particles are arranged in a regular way so solids have

a definite shape

2. Particles are packed closely together

3. Strong forces hold the particles together

Particle Theory

Liquids

1. No regular arrangement of particles. Liquids have no shape of their own, they take up the shape of the container you put them into.

2. Particles in a liquid slide over each other

3. The forces between the particles in a liquid are weaker than in a solid.

Particle Theory

Gases

1. The particles are much farther apart than in a solid or liquid

2. Particles in a gas can move quickly to fill up all available space

3. There are weak forces

between the particles in a gas.

Diffusion is the movement of particles to spread out and fill all of the available space.

Gases can diffuse quickly.

Diffusion occurs more slowly in liquids and gases because the forces holding the particles together are stronger.

Fluids: Since liquids and gases have the ability to flow they are called fluids.

Changes of State:

Examples of changes of State1.The hot steam from a shower turns back into liquid water

when it hits the cold mirror in the bathroom

2. Steam from a boiling kettle turns back to liquid water when it hits a cold window