SAMPLE LAB REPORT
10 October 2006
Boiling speed of salt water
Aim: Does salt water reach 100°C at the same speed as tap water?
Hypothesis: My hypothesis is that salt water will reach 100°C more slowly than tap water because it is thicker.
Independent: Amount of salt
Dependent: Time measured in seconds
Controlled: Amount of water; temperature of the Bunsen burner flame
Apparatus: Two each of: beaker, tripod, Bunsen burner, stop clock, thermometer.
Note: This is a sample of labelled diagram. It is not a diagram showing the experiment to determine the boiling point of salt water.
1. Fill both beakers with 200ml water from the tap.
2. Add 5g salt to one of the beakers
3. Turn on both Bunsen burners at same time.
4. Turn on both stop clocks.
5. Use thermometers to measure the temperatures in both beakers.
6. Record the time when the temperature reaches 100°C.
7. Repeat 1-7 above with 10g, 15g, 20g salt.
|Amount of Salt (in grams)||Time to 100°C (in seconds)|
Conclusion: My hypothesis was wrong. In fact, the opposite is true: the more salt there is in the water, the more quickly the water reaches 100°C. This is because ..
Evaluation: The experiment was easy to understand and to do for two students working together. However, there was a problem with controlling the two Bunsen burners to make sure they burned at exactly the same temperature.
* Not a real student.