thermal energy

Question 1

what are solids

Answer 1

solid particles are close together and are in fixed positions
-cannot be compressed
-fixed shape
-cannot flow

Question 2

what are liquids

Answer 2

liquid particles are close together and are not in fixed positions
-cannot be compressed
-no fixed shape
-can flow

Question 3

gases

Answer 3

gas particles are far apart ad are not in fixed positions
-can be compresses
-no fixed shape
-can flow

Question 4

what is conduction

Answer 4

transfer of hear energy through solids AND direct contact

Question 5

direction of heat transfer

Answer 5

heat energy always travels from hot to cold

Question 6

thermal conductors

Answer 6

substances that allows heat energy to pass through it completely

Question 7

thermal insulators

Answer 7

substances that do not allow heat energy to pass through it easily

Question 8

what is convection

Answer 8

the transfer of heat energy in fluids (gases and liquids)

Question 9

conduction and convection similarities

Answer 9

-both happen by heat causing particles to vibrate more (gain kinetic energy)
-then bumping into each other creating heat (caused by friction)
- then passing it on to the next particles and so on

Question 10

what is radiation

Answer 10

heat transfer through space, no particles required

Question 11

states of matter in this exam

Answer 11

what state is the matter in and how did it get to that matter

Question 12

what is temperature

Answer 12

measure of hotness or coldness expressed in celsius, it indicates the direction that heat energy flows

Question 13

melting point

Answer 13

temperature at which a solid turns into a liquid

Question 14

boiling point

Answer 14

temperature at which a liquid turns into a gas

Question 15

specific heat capacity

Answer 15

describes how much energy it takes to raise the temperature
of a 1KG substance
by 1 degree C

Question 16

specific latent heat

Answer 16

the amount of energy ABSORBED or RELEASED to change the state of 1kg of a substance
WITHOUT a change in temperature
ice - water
water - steam

Question 17

how does energy and latent heat relate

Answer 17

the energy is used to weaken the forces holding the particles together, not change the kinetic energy and so the temperature doesn’t change

Question 18

what is latent heat of fusion

Answer 18

-the energy required to change a substance from solid to liquid at a constant temperature
-the energy released when a substance changes from a liquid to be a solid at a constant temperature

Question 19

latent heat of vaporisation

Answer 19

-the energy required to change a substance from liquid to gas at a constant temperature
-the energy released when a substance changes state from a gas to a liquid at a constant temperature

Question 20

power

Answer 20

power, W. (watts) is a measure of the rate at which energy is transferred from one form to another

Question 21

combining specific heat capacity and latent heat

Answer 21

the total energy required to heat a substance from when it changes temperature and state can be calculated using SHC and LH
-it is energy total = specific heat energy + latent heat energy