
CSI: Chemistry Scene Investigation
This project teaches students about polar and non-polar molecules using column chromatography. A classroom has been vandalized, and students must solve the mystery of who ruined Ms. Velez's classroom. A blue liquid has been left behind at the scene. Can students figure out who dunnit?
Abstract
The lesson Chemistry Scene Investigation (CSI) is a multi-component activity that will introduce students to the chemistry “behind the scenes in forensic science.” The first part of the laboratory includes an investigation activity where the students have to separate all the components of a polluted water sample. The second part of the activity is a crime scene investigation, where students have to use the technique of column chromatography—a separation technique used to purify compounds—and determine who was the culprit. Column chromatography is widely used in many organic chemistry laboratories both in industry and academia. In the laboratory of Joseph O’Connor at the UC San Diego, we study new transformations of inorganic and organic molecules that could eventually lead to new discoveries in areas, such as, pharmaceuticals, materials, and catalysis. We employ chromatographic techniques to purify molecules in order to further elucidate structures of novel compounds. This inquiry-based activity provides a unique opportunity for students to learn new laboratory skills, typically learned in college, and gain an understanding of how science works. The incorporation of pop culture was included to capture their attention.
GRADE LEVEL: High School Chemistry (Honors and College Prep)
DURATION: Day 1: 90-minute period
Day 2: 90-minute period
LEARNING OBJECTIVES:
Students should be able to…
• Define the concept of electronegativity and polarity.
• Be able to apply the concept of polarity in order to evaluate the data they collect.
• Learn the skills necessary to run a chromatography column.
• Relate how chromatography works based on the polarity of compounds in a solution.
• Solve the mystery presented using scientific evidence to re-enforce their claims.
