Separating Substances
Materials
Dirt
Sawdust
Iron Filings
Salt
Bunsen burners or
meths burners
Filter paper
Years 7—8
Funnels
Beakers or similar
Magnets
Instructions:
Mix together:
Dirt
Sawdust
Iron filings
Salt
Discuss work ways to separate all of these substances from each other using the
equipment provided.
1.
Using magnets to take out iron filings
2.
Add water (create solution of water-soluble components)
3.
Cover with water to float off the sawdust (differential densities)
4.
Filtering to take out the dirt (physical size of particles)
5.
Boiling to evaporate the water to recover the salt the salt (relatively low boiling point of
water)
If planning to weigh components, dry the sawdust same way.
By completing this experiment students will see that by using scientific processes they can
achieve resolution in everyday challenges.