thermal energy Flashcards
(21 cards)
what are solids
solid particles are close together and are in fixed positions
-cannot be compressed
-fixed shape
-cannot flow
what are liquids
liquid particles are close together and are not in fixed positions
-cannot be compressed
-no fixed shape
-can flow
gases
gas particles are far apart ad are not in fixed positions
-can be compresses
-no fixed shape
-can flow
what is conduction
transfer of hear energy through solids AND direct contact
direction of heat transfer
heat energy always travels from hot to cold
thermal conductors
substances that allows heat energy to pass through it completely
thermal insulators
substances that do not allow heat energy to pass through it easily
what is convection
the transfer of heat energy in fluids (gases and liquids)
conduction and convection similarities
-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
what is radiation
heat transfer through space, no particles required
states of matter in this exam
what state is the matter in and how did it get to that matter
what is temperature
measure of hotness or coldness expressed in celsius, it indicates the direction that heat energy flows
melting point
temperature at which a solid turns into a liquid
boiling point
temperature at which a liquid turns into a gas
specific heat capacity
describes how much energy it takes to raise the temperature
of a 1KG substance
by 1 degree C
specific latent heat
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
how does energy and latent heat relate
the energy is used to weaken the forces holding the particles together, not change the kinetic energy and so the temperature doesn’t change
what is latent heat of fusion
-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
latent heat of vaporisation
-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
power
power, W. (watts) is a measure of the rate at which energy is transferred from one form to another
combining specific heat capacity and latent heat
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
