A temperature sensor can collect information about the heat generated when lime is mixed with water. Exothermic reactions are used in a glove heating pack. The proportions of this mixture is important. If icing sugar is added to the lime mixture the rate of heat generation changes. You can investigate the results of adding different amounts of sugar (or water) to the lime and so determine the mixture which gives out most heat for the longest time.
Beakers, insulation for the beaker, test tube, balance to weigh solids, icing sugar, quicklime, plastic gloves, interface and temperature sensor.
Connect a temperature sensor to socket 1 on the interface.
Place the solid ingredients in a beaker. Put the temperature probe in a test-tube with a measured volume of water.
Recording the data
Record for 15 minutes. Add water to the solids and stir.
Repeat the experiment using different mixtures of lime and icing sugar.
Using the results
How does the graph tell you the mixture is getting hotter?
When during the reaction is the mixture getting hotter fastest?
How long does the heating effect last for?
What might the area under each graph be a measure of?
How can you decide which mixture is the best?