Classify the following changes as physical or chemical changes
Evaporation of alcohol
Expansion of air
Chewing food
Dissolving salt in water
Cooling a mixture of air and kerosene vapour
Burning a mixture of air and kerosene vapour
Pulling copper into thin wire
Tarnishing of jewellery
Evaporation of alcohol – physical change
Expansion of air - physical change
Chewing food – physical change
Dissolving salt in water – physical change
Cooling a mixture of air and kerosene vapour – physical change
Burning a mixture of air and kerosene vapour – chemical change
Pulling copper into thin wire – physical change
Tarnishing of jewellery – chemical change
