Changes of State

Question 1

how does a substance change state

Answer 1

the substance absorbs or releases energy

Question 2

name the change of state when a solid changes into a liquid

Answer 2

melting

Question 3

what happens to particles when a solid melts

Answer 3

particles vibrate faster = move around faster = increases energy = solid pattern breaks up = becomes liquid

Question 4

name the change of state when a liquid changes into a solid

Answer 4

freezing

Question 5

what happens to particles when a liquid freezes into a solid

Answer 5

particles vibrate slower = move around slower = energy decreases = create a solid pattern = becomes solid

Question 6

what happens to particles when a liquid boils into a gas

Answer 6

???

Question 7

what happens to particles when a liquid evaporates into a gas

Answer 7

particles with the most energy leave the liquid’s surface = move away from the liquid = spread out = now a gas

Question 8

can all changes of state be reversed?

Answer 8

yes

the particles have not changed = can return to their previous state

(solid ice to liquid water / liquid water to solid ice)

it’s only the amount of energy that has changed

Question 9

boiling and evaporation change the state of particles from a liquid to a gas

what’s the difference between boiling and evaporating

Answer 9

boiling = happens at boiling point only

evaporating = happens at any temperature

Question 10

what happens to particles when a gas condenses into a liquid

Answer 10

when water vapour (gas) cools down = particles slow down = less energy = moves less = becomes liquid

????

Question 11

what happens to particles when a solid sublimes into a gas

Answer 11

particles change directly from a solid to gas

(skip being a liquid)