UNIT 2B – CALORIMETRY
Calorimetry
Apparatus Required:
- Test tube
- Boiling tube
- Water bath set at 75◦C
- Thermometer
- 2 Test tube racks : one in the water bath and one on the table
- Stearic acid
- Paraffin wax
Method:
Stearic acid:
Put some stearic acid into a test tube and place it into a rack in a water bath set at
75˚C.
Place a test tube rack on a table and put a thermometer in the test tube that
contains the acid.
Take the test tube out of the water bath and place it into the test tube rack on the
table.
Measure the temperature (ensure that it is the highest temperature before it begins
to decrease) and start a stopwatch.
Measure and record the temperature at 30 second intervals until the stearic acid
solidifies or until the temperature stops decreasing (stays the same results for 2
minutes).
Place the test tube back into the water bath and wait for it to melt before removing
the thermometer so that it doesn’t break/snap.
Paraffin wax:
Put some Paraffin into a boiling tube and place it into a rack in a water bath set at
75˚C.
Place a test tube rack on a table and put a thermometer in the boiling tube that
contains the paraffin wax.
Take the paraffin tube out of the water bath and place it into the test tube rack on
the table.
Measure the temperature (ensure that it is the highest temperature before it begins
to decrease) and start a stopwatch.
Measure and record the temperature at 10 second intervals until the stearic acid
solidifies or until the temperature stops decreasing (stays the same results for 40
minutes).
Place the boiling tube back into the water bath and wait for it to melt before
removing the thermometer so that it doesn’t break/snap.
Risk assessment of stearic acid & paraffin wax: