Students will try to solve a problem of a mysterious chemical in a barrel by performing flame tests on known cations in various compounds. Then they will test an unknown to solve the problem. I usually make the unknown strontium as it gives the best indicative color (red). You could also use Potassium Sulfate (Violet).
1. Pour a small amount of each solution into 50 mL beakers for each lab station that you wish to have.
2. I have found that soaking wood popsicle sticks in the solution overnight makes the lab much easier and the flame more brilliant.
3. Each station will have the beaker with fluid, wooden stick soaked over-night, and a bunsen burner.
4. Give the students the unknown solution once they have tested the knowns for their baseline.
To determine what metal is contained in the barrels behind the Benetti’s house, you must first perform flame tests with a variety of standards solutions of different metal compounds. Then you will perform a flame test with an unknown sample from the site to see if it matches any of the solutions you have used as standards. Be sure to keep your equipment very clean and perform multiple trials to check your work
Your company has been contacted by Julius and Annette Benetti. They are worried about some abandoned, rusted barrels of chemicals that their daughter found while playing in the vacant lot behind their home. The barrels have begun to leak a colored liquid that flows through their property before emptying into a local sewer. The Benetti's want your company to identify the compound in the liquid. Earlier work indicates that it is a dissolved metal compound. Many metals such as lead have been determined to be hazardous to your health. Many compounds of these metals are often soluble in water and therefore easily absorbed into the body