1. States of matter Particle theory
Year 8 Chemistry
States of matter
Particle theory

2. Understanding Elaboration
The properties of different states of matter can be explained in terms of the motion and arrangement of the particles.
Elaboration
Modelling of the particles
Linking energy and temperature change.
Elaboration
Modelling of the particles
Linking energy and temperature change.

3. Questions to think about
Why does ice melt?
What is dry ice, and why doesn’t it melt?
Why do car windows fog up in winter?
What are clouds made of?
What s the difference between hail and snow?
Why are there small gaps in railway lines?

4. Why do we need a model for the structure of matter?
Particle model of matter song

5. How does the particle model explain solids, liquids and gases
How does the particle model explain solids, liquids and gases? Matter can exist in three states – solid, liquid and gas Matter can exist in three states – solid, liquid and gas

7. Characteristics of Solids, Liquids and Gases
Liquids
Gases
Definite shape
No definite shape
Definite volume
No definite volume
Hard to compress
Easy to compress
Do not flow
Flow easily
Diffuse to fill all available space

8. These particles are so small that two million of them would fit into the full stop at the end of this sentence!

9. It’s not surprising that it took thousands of years before people believed that atoms exist. In fact many scientists, including Einstein, were doubtful that atoms existed until just over 100 years ago.
We can now see atoms using special hi-tech microscopes.

10. Atoms are always moving (jiggling), and it is this movement that determines whether the object is a solid, a liquid or a gas.

11. In a solid atoms jiggle around a fixed position but don’t actually move anywhere. As you heat the solid the atoms jiggle more quickly over a greater area. You can’t see the atoms moving, but the solid expands slightly!

13. We say that the solid is turning to a liquid.
If you keep heating the solid, the atoms get so much energy that they are able to leave their fixed position, sliding past each other while continuing to jiggle.
We say that the solid is turning to a liquid.

14. We say that the liquid has turned to a gas.
Further heating gives the atoms enough energy to completely break away from each other, moving in straight lines.
We say that the liquid has turned to a gas.

15. Open the link below
Open the link below

16. Experiments to be done from your text book:
6.1 Compare solids liquids and gases.
6.2 Measure volume of a shape.
6.3 Investigate diffusion.
6.4 Explaining gases.
6.5 Expansion in silids.
6.6 Expansion in liquids.

17. You now have questions to answer:
P Rem Think.
P Rem Think.
P Rem Think.
P Rem Think.
P Rem Think.
P235, 236 Summary and looking back questions
You now have questions to answer: