Year 8 Science · Unit 3 · Lesson 3

Particle Model of Physical Change

Foundation Worksheet

Name
Date
Class

Learning Goals

True or False? Fix the false ones

Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.

When ice melts, new water particles are created to fill the space.

Correct it:

T
F

A gas is easily compressed because its particles are far apart with lots of empty space between them.

Correct it:

T
F

When salt dissolves in water, it forms a new compound called sodium chloride solution, which is a chemical change.

Correct it:

T
F

In a solid, particles vibrate in fixed positions and do not move from place to place.

Correct it:

T
F

Odd one out

Circle the item that does not belong in each group. Then explain why it doesn't fit using the particle model.

#GroupYour answer (odd one + particle model reason)
1 Melting wax    Evaporating alcohol    Dissolving sugar    Burning paper
2 Solid ice    Liquid water    Steam    Hydrogen gas from a reaction
3 Particles gain kinetic energy    Particles spread further apart    Particles form new bonds    Particles move more quickly

1. Use the particle model to explain why steam (water vapour) and liquid water are both still "water," even though they look and behave very differently.

Recall 2 marks

2. The Bureau of Meteorology uses the particle model to explain rainfall. Describe what happens to water particles at the ocean surface (evaporation) and again in a cold cloud (condensation). Is either process a chemical change? Explain.

Recall 2 marks

Wrap Up

In one sentence, what was the main idea of this lesson?