Simple Combustion practical - Easy to resource

A PowerPoint with supporting instructions, starter and extension activities. Best if you use tealight candles. Encourages students to consider variables and to make accurate measurements. Students draw a graph to show their results. If students are difficult to motivate then ask them to estimate how long a candle would last in a specific volume (i.e. 300ml beaker) which they will have to produce a graph to extrapolate or interpolate to find this out. You could test a 300ml beaker at the end to test this. The extension activity promotes higher level scientific thought. It is unknown if the carbon dioxide smothers the candle or if the oxygen runs out first. Most students will say the taller candle as this will last longer!