Arson or Accident?
Story: Cameron Todd Willingham was put on trial for a 1991 house fire that killed his three children. He was found guilty and executed in 2004. While the evidence and testimony presented at his trial seemed to point toward his guilt, as the date of his execution grew near, it became clear that the evidence his conviction was based on was not scientifically sound. Students will use principles of conservation or matter, conservation of energy, thermochemistry, and introductory stoichiometry to evaluate the trial evidence.
Objectives: The student will be able to…
1. Use the law of conservation of mass to write and balance chemical equations.
2. Perform stoichiometric calculations, including determination of mass relationships between reactants and products.
3. Understand energy and its forms, including chemical, potential, chemical, and thermal energies.
4. Understand the law of conservation of energy and the process of heat transfer.
5. Use thermochemical equations to calculate energy changes that occur in chemical reactions and classify reactions as exothermic or endothermic.
6. Perform calculations involving, heat, mass, temperature change, and specific heat.
7. Use calorimetry to calculate the heat of a chemical process.
8. Understand oxidation-reduction reactions.
Product is split into student pages and teacher pages. Teacher instructions and keys are provided in the teacher pages.
Introduction Reading (Case information.)
Flames and Energy Notes (Notes: Forms of energy and Law of Conservation of Energy)
Practicing Energy Transformation Activity (Practice with energy transformations)
What is Fire? Video Questions
Evidence Notebook (Set up notebook for case.)
Worksheet: Energy Transformation (Practice with energy transformations.)
Flames and Matter Activity (Balancing equations with manipulatives.)
Conserving Mass Lab (Students confirm mass is conserved in a reaction.)
Balancing Equations Introduction (Computer activity)
Balancing Equations (Paper practice of balancing equations.)
Balancing Equations Rotation Activity (More balancing equation practice.)
Investigating the Origin Reading (Case information.)
Worksheet: Matter and Energy (Practice with balancing equations and energy transformations.)
Heat Transfer Lab (Observe convection, conduction, and radiation.)
Heat Transfer Notes (Chart for student to make notes on convection, conduction, and radiation.)
Burning at the Edges Lab (Determine the percent composition of water in a hydrous crystal.)
Calorimetry and a Candle Lab (Use a basic calorimeter and solve equations using specific heat.)
Endothermic/ Exothermic Lab (Introduce exothermic and endothermic reactions and solve equations using specific heat.)
Worksheet: Heat (Practice heat transfer vocabulary and solving equations with specific heat.)
Evidence of Arson Reading (Case information.)
Accelerants Activity (Introduce change in enthalpy and stoichiometric ratios.)
Willingham Speaks Reading (Case information.)
Up in Flames Lab (Students produce a metal oxide, define an oxidation-reduction reaction, and apply ∆H and stoichiometric ratios.)
Witnesses Reading (Case information.)
Worksheet: Redox and Enthalpy (Practice identifying a redox equation and solving problems using stoichiometric ratios.)
Defending Your Case (Writing activity.)
The Verdict/ Hurst Report (Reading and Discussion)
Execution (Reading and discussion.)
Please see the preview for a list of materials, a suggested time frame, and a sample activity.