7G - States of matter

Question 1

How are particles arranged in solids?

Answer 1

Particles are very close together and in an ordered way (strong forces of attraction). Particles in solids vibrate in fixed positions.

Question 2

Can solids change shape easily?

Answer 2

No

Question 3

Can solids change volume?

Answer 3

No

Question 4

How are particles arranged in liquids?

Answer 4

Particles are fairly close together (quite strong forces of attraction). Particles are able to move past each other.

Question 5

Can liquids change volume?

Answer 5

No. They have fixed volumes.

Question 6

Can liquids change shape easily?

Answer 6

Yes. They fit the shape of the container.

Question 7

Can liquids be easily compressed?

Answer 7

No.

Question 8

How are particles arranged in gases?

Answer 8

Particles are spread out (weak forces of attraction) and can move freely in all directions.

Question 9

Can gases change shape and volume easily?

Answer 9

Yes.

They can flow very easily and spread out to fill a container.

Question 10

Can gases be compressed quite easily?

Answer 10

Yes.

Question 11

What do you see when you observe pollen grains in water through a microscope? How is this called?

Answer 11

Pollen grains move jerkily in different directions. This is called Brownian motion.

Question 12

Why does brownian motion occur?

Answer 12

Water particles are moving all the time.

The pollen grains are small enough so that when many water particles hit one side of the pollen grain, the grain changes direction.

(in the diagram, pollen grains would be the yellow circle and water molecules the black dots)

Question 13

What is diffussion?

Answer 13

When chemicals mix together without anything moving them.

Question 14

Why does diffusion occur?

Answer 14

Because particles are always moving around in liquids and gases.

Question 15

Is diffusion faster in gases or in liquids?

Answer 15

Diffusion is faster in gases.

Question 16

What is dilution?

Answer 16

When you add water to a solution and the particles of the solution become more spread out.

(this can be seen by the colour becoming paler, for example)

Question 17

What is pressure caused by?

Answer 17

Particles hitting the walls of the container they are in.

Question 18

What could cause the pressure to increase?

Answer 18

• Container is squashed, so volume decreases, so particles will hit the walls of the container more often.
• The number of particles is increased, so there are more particles moving that hit the walls.

Question 19

What happens when pressure is increased inside a flexible container like a balloon?

Answer 19

An increase in pressure can make the volume increase. If the pressure becomes too big, it may burst.

Question 20

What happens when all the air is sucked out from a container?

Answer 20

A vacuum is created (a space with no particles).

The container may also collapse because the outside pressure is greater.