The Case of the Poisonous Pill
A girl falls ill and dies after taking a medicine that her mother gives her. Soon other deaths are reported. The common factor in all of the cases is Extra-strength Tylenol.
Loosely based on the 1982 Chicago Tylenol murders, this problem-based learning investigation requires students to use moles, percent composition, and empirical formulas to determine why people keep dying after taking Tylenol.
The student will be able to:
(A) Calculate formula/ molar mass.
(B) Calculate percent composition.
(C) Calculate empirical and molecular formulas.
(D) Define and use the concept of a mole.
(E) Use the mole concept to calculate the number of atoms, ions, or molecules of a sample of material.
1. Introduction (Reading)
- A girl dies after taking a common medication given to her by her mother. The mother says that she gave the girl Tylenol from her purse and gives you a small pill case. You want to know the identities of the other pills in the case.
2. Counting Atoms in a Formula (Notes/ Worksheet)
- Students learn to count the atoms in a formula and apply this to the formulas of several known medications.
3. Counting Atoms in a Sample (Lab/ Notes)
- Students estimate number of using mass and are introduced to the mole.
4. Extra Practice: Moles to Particles/ Particles to Moles (Worksheet)
5. Moles to Mass (Notes)
- Students convert moles to mass and determine the formula/ molar masses of several known medications.
6. Mass to Moles (Notes/ Lab - Two Versions)
- Students convert mass to moles and find the number of moles of several medications.
7. Mixed Practice: Moles/ Particles/ Mass - Worksheet
8. Percent Composition I (Lab/ Notes)
- Students find the percent composition of an egg and learn to calculate the percent composition of elements in a compound.
9. Percent Composition II (Lab)
- Students decide if two pills are identical by comparing the percent compositions of their active ingredient and binder.
10. Percent Composition Practice - Worksheet
11. Empirical Formulas (Notes/ Worksheet)
- Students learn to calculate empirical formulas to determine what medications the victim’s mother has in her purse.
12. Molecular Formulas (Notes/ Worksheet)
- Students learn to calculate molecular formulas.
13. More Victims (Reading)
- More victims appear. The investigation shifts to determine if they could have been poisoned.
14. Fatal Dose (Worksheet)
- Students use moles to calculate whether a fatal dose of a poison could fit in a Tylenol capsule.
15. Percent Composition III (Worksheet)
- Students determine the identity of the poison using percent composition.
16. Suspects I (Reading/ Worksheet)
17. Suspects II (Reading/ Worksheet)
18. The “Real” Story of the Tylenol Murders (Reading)
19. Teacher Pages
- Notes for teaching and keys