other shit

Question 1

how to tell if a chemical change has occured

Answer 1

1. a new colour has appeared.
2. heat/ light is given off.
3. bubbles/gas are formed.
4. a solid material (precipitate) has formed.
5. a new odour is produced.
   + the changes are difficult to reverse!!

Question 2

changes of state

Answer 2

melting/fusion-solid to liquid
freezing/solidification-liquid to solid
evaporation-liquid to gas
condensation-gas to liquid
sublimation-solid to gas
deposition-gas to solid

Question 3

physical change rules

Answer 3

1. the substance remains the same, even though it may change state or form.
2. no new substance has been created.
3. the change can be reversed.
4. changes of state; solid liquid and gas.

Question 4

different physical properties

Answer 4

state, colour, texture, odour, lustre, clarity, and taste.