Topic The separation challenge! Level GCSE (or for students aged 11-16) Outcomes To separate a mixture containing iron, sulfur, sand and two solid food dyes into its components Instructions for teachers: this challenge should be used after you have taught separating techniques. Students are given a range of equipment (slide 5) and then work in pairs to solve the problem. Sulfur floats! Marks are awarded according to slide 6. There is an additional help sheet to support students with carrying out the chromatography step. www.thescienceteacher.co.uk | resources for science teachers who like to think

Separation Challenge! Introduce the challenge

How many substances are in my mixture? Oops, I have a problem How many substances are in my mixture?

Your mission: Separate the mixture into its ? different substances. Iron filings Sulfur Sand Food colourings ?

You will be given: Plastic freezer bag (small) Magnet Filter paper Filter funnel Spatula Stirring rod 250 ml beaker x 2 Tongs 100 ml water in a wash bottle Magnifying glass Splint Paperclip Chromatography paper cut to size 3 small weighing boats Marker pen Measuring cylinder 50 ml

At the end of the challenge you should have: The iron, sand and sulfur in three plastic pots labelled with your names (2 marks) Have a clear chromatogram (4 marks) A tidy desk at the end (2 marks) We will weigh the mass of iron filings you have separated (4 marks)

5 minutes! Thinking and planning time: How will you do the separation? In what order should you do the separation? Which equipment will you use? How will you do the chromatography?  Top Tip! plan out what you are going to do on a piece of rough paper Too much time and help?

20 minutes Get separating! Iron filings Sulfur Sand Food colourings