Page 44 - 新思维科学学生用书7 样章

2.3 Explaining changes of state

Continued

Question

2 Describe how you had to act to illustrate the behaviour of particles as a liquid
evaporates and then boils. Think about how you behaved. Was the model a good
or a bad model for particle theory? Explain.
Gas to liquid

• As a class, arrange yourselves as if you are the particles in a gas.
• Imagine part of the room is a cold surface. As you move near to the surface you
must behave as particle theory suggests. You should start to condense to form a

liquid.
Question
3 Describe the way you had to behave to illustrate the behaviour of particles as a

gas condenses. Think about how you behaved. Was the model a good or a bad
model for particle theory? Explain.

Liquid to solid
• As a class, arrange yourselves as the particles in a liquid. Make sure you move as
particle theory suggests.
• Now imagine the liquid has been placed in a freezer. Behave as particle theory

suggests, as you become a solid.
Question

4 Describe the way you had to behave to illustrate the behaviour of particles as a
liquid freezes to form a solid. Think about how you behaved. Was the model a
good or a bad model for particle theory? Explain.

• How did you learn and remember the structure of solids, liquids and gases as
states of matter?

Summary checklist

I can describe how particles behave, depending on how much energy they have.

I can explain that energy can be transferred to or from particles.
I can describe the effects of the energy on the forces holding the particles
together.

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