C2 State and changes of state

Question 1

Solids have a set shape because the ___________ vibrate in a fixed position.

Answer 1

Particles

Question 2

Solids have a set volume (cannot be compressed) because the particles… vibrate in a fixed position move freely are close together are spaced out

Answer 2

are close together

Question 3

Liquids have a variable shape because the particles…

Answer 3

move freely

Question 4

Liquids have a set volume (cannot be compressed) because the particles…

Answer 4

are close together

Question 5

Gases have a variable shape because the particles…

Answer 5

move freely

Question 6

Gases have a variable volume (they can be compressed) because the particles…

Answer 6

are spaced out

Question 7

Liquids cannot be compressed because the particles… cannot move freely move freely are spaced out are closely packed

Answer 7

are close together

Question 8

Substance X has a set shape and fixed volume so it must be a… solid liquid gas

Answer 8

solid

Question 9

Substance Z has a variable shape and variable volume so it must be a…

Answer 9

gas

Question 10

Substance Y has a variable shape and fixed volume so it must be a…

Answer 10

liquid

Question 11

Gasses can be compressed because the particles…

Answer 11

are spaced out

Question 12

Liquids take the shape of their container because the particles…

Answer 12

move freely

Question 13

Solids have a set shape because the particles…

Answer 13

vibrate in a fixed position

Question 14

Using the idea of particles explain why solids and liquids are difficult to compress.

Answer 14

The particles are already closely packed together

Question 15

Using the idea of particles explain why liquids and gasses have a variable shape.

Answer 15

The particles can move freely

Question 16

Using the idea of particles explain why gasses can be compressed.

Answer 16

The particles in a gas are spaced out

Question 17

Using the idea of particles explain why solids have a set shape.

Answer 17

The particles in a solid are in a fixed position

Question 18

When a solid turns into a gas, we call this… evaporation solidification condensation sublimation

Answer 18

sublimation

Question 19

When a gas turns into a solid, we call this…

Answer 19

sublimation

Question 20

When a gas turns into a liquid, we call this…

Answer 20

condensation

Question 21

When a liquid turns into a gas, we call this…

Answer 21

evaporation

Question 22

When a gas condenses to form a liquid, the particles which it contains… get larger move closer together get smaller move further apart

Answer 22

move closer together

Question 23

Solid carbon dioxide turns into a gas without forming a liquid. This is known as…

Answer 23

sublimation

Question 24

When a solid turns into a liquid, we call this…

Answer 24

melting

Question 25

When a liquid turns into a solid, we call this...

Answer 25

solidification

Question 26

The boiling point of pure water is...

Answer 26

100 ˚C

Question 27

Explain using the idea of particles what happens when a liquid changes into a gas.

Answer 27

The particles gain energy and the move further apart

Question 28

Explain using the idea of particles what happens when a solid changes into a liquid.

Answer 28

The particles gain energy and they start to move freely

Question 29

Explain using the idea of particles what happens when a gas changes into a liquid.

Answer 29

The particles lose energy and move closer together

Question 30

Explain why the volume of a gas decreases when the gas is cooled. Use these words in your answer: energy, particles.

Answer 30

The particles lose energy, slow down and become slightly closer together

Question 31

Explain why it would be dangerous to heat a sealed glass bottle of air. Use these words in your answer: pressure, energy, particles.

Answer 31

The particles gain energy, get faster and the pressure increases. The bottle could explode.

Question 32

Explain using the idea of particles what happens when a liquid changes into a solid.

Answer 32

The particles lose energy and stop moving freely

Question 33

Explain why the volume of a piece of iron increases when the metal is heated.

Answer 33

The particles gain energy, vibrate faster in their fixed position and get slightly further apart

Question 34

Room temperature is approximately...

Answer 34

20 ˚C

Question 35

Substance V has a melting point of -16 ˚C and a boiling point of 58 ˚C so at room temperature substance V would be a... solid liquid gas

Answer 35

liquid

Question 36

Substance W has a melting point of -175 ˚C and a boiling point of -169 ˚C so at room temperature substance W would be a...

Answer 36

gas

Question 37

Substance Y has a melting point of 56 ˚C and a boiling point of 375 ˚C so at room temperature substance Y would be a...

Answer 37

solid

Question 38

Substance X has a melting point of 12 ˚C and a boiling point of 134 ˚C so at room temperature substance X would be a...

Answer 38

liquid

Question 39

Substance Z has a melting point of -265 ˚C and a boiling point of -7 ˚C so at room temperature substance Z would be a...

Answer 39

gas

Question 40

A chemical change is... water boiling ice melting cake baking oil heating

Answer 40

Cake baking The others are physical processes

Question 41

Which one of the following is not a chemical change? plants respiring coal burning wax melting glue hardening

Answer 41

wax melting is a physical process

Question 42

Explain why the volume of a lump of aluminium decreases when the metal is cooled.

Answer 42

The particles lose energy, vibrate slower in their fixed position and move even closer together