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Investigating the rate of decomposition of hydrogen peroxide
Background
Hydrogen peroxide decomposes to produce oxygen gas and water. The reaction
can be catalysed by yeast.
2H202(aq) O 2(g) +2H2O(l)
One way of measuring the rate is to time how long it takes for a disc of filter
paper to rise a specific distance in a test tube containing hydrogen peroxide
solution.
Practical Techniques
You will need to find out about how to make up accurate solutions.
Where to start
Plan an experiment to investigate the effect of changing the concentration of the
hydrogen peroxide and the yeast on the rate of the reaction.
Possible Investigations
• Investigate the reaction at different temperatures to determine the effect of
temperature on the rate and hence determine the activation enthalpy for
the reaction.
• Investigate the effect of other potential catalysts.
• Investigate the effect of pH on the reaction.
• Investigate a different technique for monitoring the rate of the reaction –
possibilities are – titration, measurement of oxygen production
Sources of Information
• Woods G., Hydrogen Peroxide, Chemistry Review, September 1996
• Denby D., Decomposing Hydrogen Peroxide, Chemistry Review, (early
issue –exact date unknown)
