chemistry - states of matter & mixtures: states of matter (2.1 - 2.4)

2.1 solid, liquid & gas - arrangement, movement & relative energy of particles

2.2 names of state changes

solid → liquid = melting

liquid → solid = freezing

solid → gas = sublimation

gas → solid = deposition

liquid → gas = evaporation/boiling

gas → liquid = condensing

2.2 physical vs chemical changes

physical/chemical:

• can be reversed/can’t be reversed

• chemical properties of substance don’t change/do change

• particles don’t change/do change

  • only arrangement, movement & amount of stored energy of particles changes

attraction between particles

weak forces of attraction

2.3 changes in arrangement, movement & energy of particles - melting

particles gain energy & vibrate more

energy transferred from surroundings → particles

overcome attractive forces - particles move around each other, randomly arranged

2.3 changes in arrangement, movement & energy of particles - freezing

particles lose energy & slow down

energy transferred from particles → surroundings

attractive forces form - particles only vibrate, regularly arranged

2.3 changes in arrangement, movement & energy of particles - boiling

particles gain energy & move faster

energy transferred from surroundings → particles

overcome attractive forces - particles move fast in all directions, far apart

2.3 changes in arrangement, movement & energy of particles - condensing

particles lose energy & slow down

energy transferred from particles → surroundings

attractive forces form - particles move slower, close together

2.4 predicting physical state of substance

below meting point = solid

between melting & boiling point = liquid

above boiling point = gas