States of Matter

Question 1

The particle model (sometimes also called the kinetic model) has 3 main assumptions.

Answer 1

small, inelastic, spheres

Question 2

solid

Answer 2

1. strong attractive forces
2. fixed position
3. vibrate in position
4. defined shape
5. defined volume

Question 3

liquid

Answer 3

1. weak attractive forces
2. not in a fixed position
3. particles are free to move
4. flow to fit a container
5. definite volume

Question 4

solid - liquid process

Answer 4

As the substance is heated, the particles gain energy and vibrate faster and faster. Eventually, the particles have so much energy that they can overcome the forces holding them together, and the substance melts into a liquid.

Question 5

liquid - gas

Answer 5

As heat is applied to a liquid, the particles gain kinetic energy and move faster. With enough energy they can break the forces of attraction between the molecules. At this point the liquid would boil into a gas.

Question 6

what do we mean by fixed volume?

Answer 6

If the gas is trapped within a container that cannot expand, it means that the volume of the gas is fixed, and so the pressure inside the container increases.

Question 7

gas - liquid

Answer 7

In gases, the particles have enough energy to overcome the attractive forces between them, and so spread out randomly.
If the temperature is lowered, they will no longer be able to overcome these attractive forces, and the particles move closer together, and turn into a liquid.

Question 8

melting point

Answer 8

The temperature at which a solid converts into a liquid

Question 9

boiling point

Answer 9

The temperature at which a liquid converts into a gas

Question 10

gas

Answer 10

1. very weak attractive forces
2. not in a fixed position
3. particles are free to move
4. no definite shape
5. no definite volume