Unit 9: Matter

Sub-topic 9.3: What is matter made of?Space between particles.

Objective of the lessonAt the end of the lesson, students should be able to:give a reason, why diffusion occurs.recall the state of matter that has less space

between particles.recall the state of matter that has a lot of space

between particles.give reason, why diffusion is fastest in gas but

slowest in solid.measure volume using measuring cylinder

correctly

Recap previous lesson1. What does the word ‘diffusion’ mean?

The movement of particles of one substance through the particles of another substance.

2. In what direction does the particles diffuse? The particles diffuse in all direction.

Recap previous lessonIn the practical activity that you and your group have done in the previous lesson showed the different rate /speed of diffusion in solid liquid and gas.

3. Among these three states of matter, which state diffuse the fastest?Gas.

4. Among these three states of matter, which state diffuse the slowest? Solid.

Why do particles diffuse?

To answer that question, you will do Practical

Activity 9.5: Space between Particles.

Collect your apparatusEach group should collect/have:2 measuring cylinder1 bottle of ethanol1 bottle of distilled water1 container of substance A1 container of substance B1 bottle of salt1 plastic spoon 1 stirring rod

ONCE YOUR GROUP FINISH

THE PRACTICAL,

WRITE DOWN YOUR

FINDINGS ON THE TABLE

PROVIDED ON THE

WHITEBOARD

Make sure that your eyes are on the same level as the lower meniscus of the substance or liquid you are measuring.

You may start now! You have 10 minutes to do your practical

activity

Practical Activity 9.5: Space between particles

Practical Activity 9.5: Space between particles

Why do particles diffuse?  Particles diffuse because there is space

between the particles. Also the particles must be moving.Look at the diagrams of the particles in a gas,

a liquid and a solid.

Particles in a gasThere is a lot of space between gas

particles.

Particles in a liquidThere is space between liquid particles, but

the space is less than in gas

Particles in a solidThere is only a small space between the

particles in solids.

Diffusion in gases is faster than diffusion in liquids because the space between gas particles is more than the space in liquid particles.

Diffusion in solids is slower than diffusion in liquids because the space in solid particles is less than space in liquid particles

Therefore, diffusion happened the fastest in gas and slowest in solid because there is a lot of space in gas but less space is available in solid.

SUMMARYPUT AWAY YOUR NOTES FIRST

SUMMARY1. Why do particles diffuse?2. In which state of matter (solid, liquid or gas)

will you find a lot of space between particles?

3. In which state of matter (solid, liquid or gas) will you find a small of space between particles?

4. Why do gas particles diffuse faster than solid particles?

THE ENDTHANK YOU