|Senior Chemistry Discrepant Event
Title: Dust Can Explosion – Lycopodium Powder Combustion
Purpose: To show the relationship between the rate of a reaction and the surface area available for the reaction.
Grade Level: Grade 12 University Preparation (SCH4U)
Topic from Ontario Curriculum: Energy Changes and Rates of Reaction unit.
Specific Expectation - explain how factors such as temperature, surface area, nature of reactants, catalysts, and concentration control the rate of chemical reactions.
Theory: When you blow the powder out of the funnel, the powder is dispersed into the air. As the powder touches the candle, it ignites and the entirety of the airborne powder catches on fire. The dispersed powder has more surface area than the powder sitting together in the funnel and is able to react and therefore ignite.
Materials: metal can, lycopodium powder, funnel, hose, candle, matches.
Procedure: Setting up apparatus:
- punch a hole in the bottom of a metal can
Hints for Success: Make sure you show students that lycopodium powder will not ignite when placed in a compact state.
Safety Considerations: Keep away from heat or ignition source.
DO NOT BREATHE DUST.