The Particle Model Of Matter Worksheet printable pdf download

The Particle Model Of Matter Worksheet

5.1

The Particle Model of Matter

More than 2000 years ago in Greece, a philosopher named

Democritus suggested that matter is made up of tiny particles too

small to be seen. He thought that if you kept cutting a substance into

smaller and smaller pieces, you would eventually come to the

smallest possible particles—the building blocks of matter.

Many years later, scientists came back to Democritus’ idea and

added to it. The theory they developed is called the

particle model

of matter.

LEARNING TIP

There are four main ideas in the particle model:

Are you able to explain the

1. All matter is made up of tiny particles.

particle model of matter in

your own words? If not,

re-read the main ideas and

examine the illustration

that goes with each.

2. The particles of matter are always moving.

3. The particles have spaces between them.

4. Adding heat to matter makes the particles move faster.

heat

Scientists find the particle model useful for two reasons. First,

it provides a reasonable explanation for the behaviour of matter.

Second, it presents a very important idea—the particles of matter

are always moving. Matter that seems perfectly motionless is not

motionless at all. The air you breathe, your books, your desk, and

even your body all consist of particles that are in constant motion.

Thus, the particle model can be used to explain the properties of

solids, liquids, and gases. It can also be used to explain what happens

in changes of state (

on the next page).

Figure 1

5.1

The Particle Model of Matter

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The Particle Model Of Matter Worksheet