DrDAQ is a versatile instrument that connects to the USB port of any PC. Using the supplied PicoScope software it can be used as an oscilloscope, spectrum analyzer and signal generator.
It can be seen from Figure 2 below that the oxygen level makes a steady fall over the 24 hours showing the uptake of oxygen in the reaction which results in rusting.
You should also be able to see that rusting has taken place by the appearance of the brownish-orange oxide coating that will have formed on the steel wool.
The average room temperature for this experiment was around 21ºC
Figure 2 Graph of oxygen level with time
KS3 Science — Sc3 Patterns of behaviour
Metals
Pupils should be taught: how metals react with oxygen, water, acids and oxides of other metals, and what the products of these reactions are.
Pupils should be taught: Chemical reactions — about different types of chemical reaction, including neutralisation, oxidation, reduction and thermal decomposition, and examples of how these are used to make new materials.
This experiment was written by Chris Butlin, Sutton-Upon-Derwent, York.
If you have any comments about this experiment or suggestions for improvements please e-mail experiments@picotech.com