At a Glance


  • STEM
  • Chemistry

Instructional Level

  • College & CEGEP
  • University


  • General Chemistry

Tasks in Workflow

Social Plane(s)

  • Group
  • Whole Class

Type of Tasks

  • Discussing
  • Solving problems

Technical Details

Class size

  • Small (20-49)
  • Medium (50-99)


  • Single class period (< 90 mins)

Instructional Purpose

  • Application & knowledge building


In this activity, students are presented with a case study in which the challenge is to identify the compound responsible for an explosion in a laboratory (and in doing so, identify the individual behind the explosion).

Working in pairs, students will determine molar masses, % mass composition, and empirical formulas for various compounds in order to eliminate all but one compound (and therefore suspect).

Students then vote on the guilty party. Groups that voted for different suspects join forces to collaborate and compare their work. In these larger groups, students discuss their reasoning before coming to a conclusion for a second vote.

Instructional Objectives

To promote development of skills required to solve complex problems including the following: knowledge application, analysis and evaluation of solution. Students learn to identify substances based on clues such as molar mass.

Workflow & Materials


Activity Workflow

View on CourseFlow

Contributor's Notes

Adamo R. Petosa

Adamo R. Petosa

Dawson College, Montreal


Stay tuned.


Stay tuned.


Stay tuned.

Applied Strategies


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