Year 10 Explore Rates of Reaction With Combustion

Thursday, March 17, 2022

Summer school at Assumption College English Program starts with a bang for upper school chemistry students, well maybe more of a woosh.

The summer chemistry program started with a closer look at the standard test for oxygen which reveals that it is really about rate of reaction. Relighting a glowing wooden splint is the classic test for oxygen gas. The point explored in the lab was that oxygen in the atmosphere is what keeps the wood glowing as a combustion reaction is happening and that the increased concentration of oxygen can cause the reaction to speed and release heat more rapidly to the point that the wood relights. Students also looked at the reaction that was used to produce the oxygen, the decomposition of hydrogen peroxide. Finding out that this reaction is too slow to produce much oxygen with hydrogen peroxide alone they saw the effect of adding a catalyst to speed up the reaction. Students also investigated how concentration alters the rate of this reaction. Taking this idea to its natural conclusion was a set of experiments and demonstrations showing how sugar can be used as a fuel but that getting the concentration of oxygen higher makes a big difference.

The students finished this off with making a mixture of a chemical that produces oxygen with the sugar and testing how well it combusts. The students learned a lot, had great fun and are excited to see what happens when we use this mix to make rocket engines by dialing up the pressure by confining the fuel into a constricted tube. Watch out Space X!

Written by Mr Michael Lams