Particles

Question 1

Is a change of state physical or chemical

Answer 1

Physical- no new substances produced
(Mass always stays same)

Question 2

How to calculate density

Answer 2

Density = mass/ volume

Question 3

What is density measured in

Answer 3

Kg/ m cubed

Question 4

What is the temperature of a substance based on

Answer 4

Average kinetic energy of its particles

Question 5

True or false, temperature changes during change of state

Answer 5

False- it doesn’t change

Question 6

What is internal energy

Answer 6

Total kinetic and potential energy of particles in substance

Question 7

What is potential energy

Answer 7

How far away particles are
More heat= particles further away= more potential energy

Question 8

What is density a measure of

Answer 8

How much mass there is in a given volume of a substance
Density= mass/ volume

Question 9

What special piece of equipment is used to find volume of irregular object

Answer 9

Eureka can

Question 10

Name of change of state from gas to solid

Answer 10

Deposition

Question 11

Name of change of state from solid to gas

Answer 11

Sublimation

Question 12

Sublimation vs deposition

Answer 12

Both= changes of state
Deposition= gas to solid
Sublimation= solid to gas

Question 13

Evaporation vs boiling (both changes of state from liquid to gas)

Answer 13

Evaporation:
No bubbles
Happens at surface of liquid
Happens at temperatures below boiling point

Boiling:
bubbles
Happens throughout liquid
Only happens at boiling point temperature

Question 14

Why does temperature increase when a substance is heated (without changing its state)

Answer 14

Particles gain kinetic energy and move faster
This increases temperature as temperature is average kinetic energy of the particles in the substance

Question 15

What is specific latent heat

Answer 15

Energy required to change state of 1kg of substance without changing its temperature

Question 16

Examples of specific latent heat

Answer 16

Boiling water
Melting ice
Thermoregulation (sweat evaporating)

Question 17

2 types of specific latent heat

Answer 17

Fusion (melting/ freezing)
Vaporisation (boiling/ condensing)

Question 18

Which needs more energy, specific latent heat of fusion or vaporisation

Answer 18

Vaporisation

Question 19

Equation linking specific latent heat, energy and mass

Answer 19

Specific latent heat = energy/ mass

Question 20

Specific latent heat of fusion meaning

Answer 20

Energy required to melt/ freeze 1kg of substance without changing its temperature

Question 21

Specific latent heat of vaporisation meaning

Answer 21

Energy required to boil/ condense 1kg of substance without changing its temperature

Question 22

What is pressure in a gas created by

Answer 22

Particles colliding randomly with walls of container and exerting a force
They collide at right angles to container walls
They move in straight lines but randomly

Question 23

Relationship between pressure and temperature (when mass and volume of gas in sealed container is constant)

Answer 23

Pressure increases proportionally to temperature

Question 24

Relationship between pressure and volume of gas (at fixed mass and constant temperature)

Answer 24

Inversely proportional
If volume doubles then pressure halves etc

Question 25

Which out of chemical and physical changes can easily be reversed

Answer 25

Physical but not chemical

Question 26

True or false, mass remains constant during both chemical and physical changes

Answer 26

True

Question 27

Why does pressure increase if temperature of gas increases in sealed container (volume is constant)

Answer 27

Particles move faster so hit surfaces with more force Number of these impacts per second increases so more overall force

Question 28

Equation linking pressure, volume and constant

Answer 28

Pressure= constant/ volume

Question 29

Why does temperature of gas increase when it's compressed quickly

Answer 29

Requires force to be applied to gas so work is done on gas This energy gained by the gas isn't transferred quickly enough to the surroundings

Question 30

Latent heat of vaporisation vs fusion

Answer 30

Fusion is energy required to melt Vaporisation is energy required to evaporate

Question 31

Particles in a gas are constantly moving in... directions at... speeds

Answer 31

Random

Question 32

Explain why if volume of fixed mass of gas at constant temperature decreases pressure increases

Answer 32

Particles travel less far to collide with walls of container So more impacts (collisions) per second and total force of impact increases Vice versa if volume increases where pressure would then increase

Question 33

Equation linking pressure, volume and constant

Answer 33

Pressure x volume = constant (Pressure and volume are inversely proportional)