Your task• You have been given a bag of stuff swept up off the floor• Your task is to separate it into individual substances• In the bag there is: – Sand – Salt – Iron filings – Benzoic Acid• You must report the mass of each substance that you recover and compare the total mass recovered to the mass of mixture that you started with.
Make a plan• Before you start, make a plan and write it down• How are you going to separate the mixture?• The following pages will give you some information about each substance
Salt• You put it on your food• It dissolves in water.
Iron filings• These are small pieces of iron – what you’d get if you used a file on an iron bar• They don’t dissolve in water• They are magnetic
Benzoic acid• Used as a food preservative and in athlete’s foot cream• Benzoic acid dissolves in boiling water but re-solidifies in cold water
Equipment available• 2x beakers • Distilled water• Plastic cups for • Hot plate separated substances • Tongs• Stirring rod• Filter paper and funnel• Erlenmeyer flask• Magnet
Safety• Wear goggles AS SOON AS YOU START THE LAB – until your WHOLE GROUP is finished• Be careful with the hot plate – don’t burn yourself.• Benzoic Acid is HARMFUL – wear gloves and wash your hands when you finish the lab
Before you begin• Show your teacher your plan, or procedure.• It must be complete and have all details included.• It must be signed by the teacher BEFORE YOU START.• This is for your safety – once your plan is approved, do not change it without approval from the teacher.
Results tableMass of mixture at start: ___________ Substance Mass Sand Iron Benzoic acid Salt