Lesson Starter 1 Draw a particle diagram which

Lesson Starter 1. Draw a particle diagram which shows a change of state from: a) A solid to a liquid b) A liquid to a gas 2. What is the process called when: a) A solid changes into a liquid b) A liquid changes into a solid c) A liquid changes into a gas d) A gas changes into a liquid

What’s the matter? Lesson 7

Lesson 7 - Learning Intention To learn what happens to the particles during a change of state

Group Discussion • Look at the cartoons on page 15 • Discuss the statements in your group and decide (as a group which one you think is correct and why)

Can particles help us understand what happens during state changes?

David No, there are different kinds of particle in solid candle wax and melted candle wax

Gary I think the particles are the same, they just move differently

Lisa The heat from the flame has made the candle melt- that means there are no particles left

Changing state • When an object changes state- the particles all remain the exact samethey just move differently • In order to move particles need ENERGY

Energy • If particles are given more energy- they can move faster • Take away the energy and the particles move slower

Solid to liquid • Heating provides energy and particles move faster • Particles in a solid move faster they can break free from solid and flow into a liquid • Particles in a liquid have more energy and have moved apart from each other

Liquid to Solid • Cooling a substance causes the particles to move slower • Particles can no longer move freelysolid

Liquid to Gas • Heating liquids provide enough energy for the particles to break free and leave the surface of the liquid • They become a gas • The particles are fast moving and have lots of space

Gas to Liquid • Cooling the gas causes the particles to slow down • Gas turns back to liquid

Textbook questions Starting science 1 (purple books) Read the information on page 56 and answer the questions at the bottom of the page