Practical plan for Unit 2: Aim B

Aim
To construct cooling curves and accurately study the rate of cooling of paraffin
wax and stearic acid using calibrated equipment.




Equipment

- Hot plate
- Ice
- Digital thermometer
- Timer
- Beakers
- Scales
- 50g paraffin wax
- 50g stearic acid
- Spatulas



Variables
Dependent: Temperature
Independent: Time
Controls: Mass of samples, type of thermometer, medium in which cooling is
occurring in
Risk assessment

Hazard Risk Precautions
Hot plate Burns, fire risk Handle with care and
turn off when not in use
Melted paraffin wax Burns Handle with care
Melted stearic acid Irritant Gloves, goggles
Glassware Breakages, cuts Handle with care




Brief method
- Place substance, either paraffin wax or stearic acid into beaker on
hot plate
- Allow solid to melt fully

- Place digital thermometer and record temp
- Place in ice bath and record temperature at 30s intervals
- Perform repeats