change p2

Question 1

purity of substances

Answer 1

has a fixed mp and bp at room temperature and a pressure
check by either fixed mp and bp or chromatography (only 1 spot in chromatogram)
pure substance needed as impure ones can bring about undesired consequences e.g. diarrhoea , food poisoning etc

Question 2

physical methods of separation

Answer 2

magnetic separation
sublimation
using suitable solvents
filtration
crystallisation
evaporation to dryness
simple distillation
fractional distillation
separating funnel