topic 3 - particle model of matter: changes of state and the particle model

Question 1

What is the equation which links density, mass and volume?

Answer 1

density = mass/volume

Question 2

What is the symbol for density?

Answer 2

ρ

Question 3

What is the symbol for mass?

Answer 3

m

Question 4

What is the symbol for volume?

Answer 4

V

Question 5

What are the units for density?

Answer 5

kg/m^3

Question 6

What are the units for mass?

Answer 6

kilograms (kg)

Question 7

What are the units for volume?

Answer 7

m^3

Question 8

How are particles arranged in a material with high density?

Answer 8

Close together.

Question 9

When you compress a material, what happens to its density?

Answer 9

It increases.

Question 10

What are the three states of matter?

Answer 10

Solid, liquid and gas.

Question 11

Which state of matter generally has the highest density?

Answer 11

Solids.

Question 12

How do particles move in a solid?

Answer 12

They vibrate in fixed positions.

Question 13

Do particles have a lot of energy in solids?

Answer 13

No (so they can only vibrate in fixed positions).

Question 14

How do the forces of attraction in solids and liquids compare?

Answer 14

Solids have stronger forces of attraction than liquids.

Question 15

How are particles arranged in a liquid?

Answer 15

Close together, but can move past each other, and form irregular arrangements.

Question 16

How do particles move in a liquid?

Answer 16

In random directions at low speeds.

Question 17

How does the energy of particles in solids and liquids compare?

Answer 17

Particles in liquids have more energy than in solids.

Question 18

What are forces of attraction in gases like?

Answer 18

Very weak - almost none.

Question 19

Do gas particles have more or less energy than liquids and solids?

Answer 19

More energy.

Question 20

How do particles move in gases?

Answer 20

In random directions at high speeds.

Question 21

What is the density of a gas like?

Answer 21

Low.

Question 22

When a substance changes state, what happens to its mass?

Answer 22

It is conserved (stays the same).

Question 23

Is a change of state a physical or chemical change and why?

Answer 23

Physical change - the material recovers its original properties if the change of state is reversed.

Question 24

What is the change of state from solid into liquid called?

Answer 24

Melting.

Question 25

What is the change of state from liquid into solid called?

Answer 25

Freezing.

Question 26

What is the change of state from liquid into gas called?

Answer 26

Boiling OR evaporating.

Question 27

What is the change of state from gas into liquid called?

Answer 27

Condensing.

Question 28

What is the change of state from solid into gas called?

Answer 28

Sublimating.