changes of state and internal energy stores

Question 1

to change a substances state, you need a change in the energy in the _________ of the particles

Answer 1

internal energy stores

Question 2

how do you transfer energy to internal energy stores

Answer 2

by heating

Question 3

a substance’s energy in its internal energy store is the

Answer 3

total energy of all particles in that substance

Question 4

when you heat a substance, you transfer energy to the particles of the substance- so you will always ____ the energy in the internal energy store of the substance

Answer 4

increase

Question 5

how can the temperature of a substance be measured (2)

Answer 5

kelvin scale (K)
degrees celsius

Question 6

If a substance is changing its state, its temperature will

Answer 6

stay constant

Question 7

for water at standard atmospheric pressure, what is boiling and melting point at *C

Answer 7

b- 100
m- 0

Question 8

as substances cool, energy is transferred ____ from them so they ___ energy from their _____

Answer 8

away
lose
internal energy store

Question 9

condensation happens at the same temperature as

Answer 9

boiling

Question 10

the forces between particles become ____ as particles move closer together

Answer 10

stronger

Question 11

condensation is

Answer 11

gas to liquid

Question 12

solidification is

Answer 12

liquid to solid

Question 13

melting is

Answer 13

solid to liquid

Question 14

boiling is

Answer 14

liquid to gas

Question 15

solid to liquid is

Answer 15

melting

Question 16

liquid to gas is

Answer 16

evaporating

Question 17

gas to liquid is

Answer 17

condensation

Question 18

liquid to solid is

Answer 18

freezing

Question 19

particles in solids are : (3)

Answer 19

Tightly packed
Held in fixed pattern
Vibrate about fixed positions

Question 20

particles in liquids are : (2)

Answer 20

Tightly packed
Can slide over each other

Question 21

particles in gases are : (2)

Answer 21

Very spread out
Move with rapid, random motion

Question 22

PRACTICAL - obtain a temperature–time graph to show the constant temperature during a change of state

Answer 22

Place the ice cubes in the beaker (it should be about half full)

Place the thermometer in the beaker

Place the beaker on the tripod and gauze and slowly start to heat it using the bunsen burner

As the beaker is heated, take regular temperature measurements (e.g. at one minute intervals)

Continue this whilst the substance changes state (from solid to liquid)