Btec Applied Science
Unit 2b - Calorimetry
Undertaking calorimetry to study cooling curves
Before starting our calorimetry experiment, we first had to calibrate our thermometer.
Calibration of a thermometer:
The definition of calibration is to “correlate the readings of an instrument with those
of a standard in order to check the instruments accuracy”. [1]
To calibrate our liquid thermometer, we used 150ml of distilled water for the boiling
thermometer test and 3 ice cubes for the freezing point thermometer test. We used
the same thermometer for both tests, but waited for it to return to room temperature
before starting the next test.
For the boiling test, we followed this method:
1. Measure 150ml of distilled water in a measuring cylinder and pour into a
beaker
2. Set up a bunsen burner and a tripod with a heat mat on top of it
3. Place the beaker with the water in it on top of the tripod and turn on the
bunsen burner
4. Hold the thermometer in the water (make sure it does not touch the sides or
bottom of the beaker - this is because touching the sides can fracture the
glass of the thermometer and does not allow correct measurement)
5. Wait for the water to show signs of boiling (e.g. bubbling, steaming)
6. Check the reading on the thermometer
7. When the water has reached boiling point, the thermometer should read
100℃
8. Record the temperature 3 times, a minute apart
1
, Btec Applied Science
Unit 2b - Calorimetry
For the freezing test, we followed this method:
1. Place 3 ice cubes in a beaker
2. Check the thermometer is at room temperature and then place it into the ice
cubes
3. Gently swirl the thermometer around the ice cubes until the reading states
that it is at 0℃
4. Make sure the thermometer does not touch the sides or bottom of the beaker
- this is because if it does it could fracture the glass and cause inaccurate
readings
5. Record the temperature 3 times, a minute apart
Results:
Thermometer Temperature Temperature Temperature
(℃) (℃) (℃)
1 2 3 Average
Boiling water 99.5 100 100 99.8
(liquid
thermometer)
Ice water 0 0 0 0
(liquid
thermometer)
As you can see from the results, the thermometer we used was very accurate, the
freezing point being 0℃ and the boiling point almost being 100℃. Now we have
calibrated the thermometer, we can move onto the calorimetry.
2
Unit 2b - Calorimetry
Undertaking calorimetry to study cooling curves
Before starting our calorimetry experiment, we first had to calibrate our thermometer.
Calibration of a thermometer:
The definition of calibration is to “correlate the readings of an instrument with those
of a standard in order to check the instruments accuracy”. [1]
To calibrate our liquid thermometer, we used 150ml of distilled water for the boiling
thermometer test and 3 ice cubes for the freezing point thermometer test. We used
the same thermometer for both tests, but waited for it to return to room temperature
before starting the next test.
For the boiling test, we followed this method:
1. Measure 150ml of distilled water in a measuring cylinder and pour into a
beaker
2. Set up a bunsen burner and a tripod with a heat mat on top of it
3. Place the beaker with the water in it on top of the tripod and turn on the
bunsen burner
4. Hold the thermometer in the water (make sure it does not touch the sides or
bottom of the beaker - this is because touching the sides can fracture the
glass of the thermometer and does not allow correct measurement)
5. Wait for the water to show signs of boiling (e.g. bubbling, steaming)
6. Check the reading on the thermometer
7. When the water has reached boiling point, the thermometer should read
100℃
8. Record the temperature 3 times, a minute apart
1
, Btec Applied Science
Unit 2b - Calorimetry
For the freezing test, we followed this method:
1. Place 3 ice cubes in a beaker
2. Check the thermometer is at room temperature and then place it into the ice
cubes
3. Gently swirl the thermometer around the ice cubes until the reading states
that it is at 0℃
4. Make sure the thermometer does not touch the sides or bottom of the beaker
- this is because if it does it could fracture the glass and cause inaccurate
readings
5. Record the temperature 3 times, a minute apart
Results:
Thermometer Temperature Temperature Temperature
(℃) (℃) (℃)
1 2 3 Average
Boiling water 99.5 100 100 99.8
(liquid
thermometer)
Ice water 0 0 0 0
(liquid
thermometer)
As you can see from the results, the thermometer we used was very accurate, the
freezing point being 0℃ and the boiling point almost being 100℃. Now we have
calibrated the thermometer, we can move onto the calorimetry.
2