Micro Mole Rockets
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Introducing limiting/excess reagents is always a challenge for high school chemistry students. They have just mastered basic principles of stoichiometry, and the idea of reactions where one reactant is present in excess takes some effort to comprehend. This lab is an excellent an introduction to limiting/excess reagents, where students turn the bulb of a plastic Beral-style pipette into a micro-scale rocket. Different ratios of hydrogen/oxygen are collected in the bulb, and the most explosive mixture used to shoot the rocket across the room.
Students transfer gases from the syringes to the rockets and perform a 'pop test' to evaluate the explosiveness of different ratios of oxygen:hydrogen.
The most reactive mixture is fired from the launch pad - a modified BBQ igniter, which generates a spark across a gap between two wires.