Heating Curve of Water Lab Activity
Lab: Phase Change
Chemistry: Students will investigate that the change from one phase of matter to another
involves a gain or loss of energy. This will be done through measuring data and analyzing the
constructed graph.
Materials:
1.
2.
3.
4.
5.
6.
7.
Hot plate
600-mL beaker
Thermometer
Thermometer clamp
Ring stand
200 mL of distilled water
Ice cubes
Procedures:
1. Get approximately 200 ml of ice and 200 ml of water into the 600 ml beaker.
2. Set up a data table like the one provided to record both time and temperature.
Record the temperature every 5 minutes. Start with 0 min.
3. Place the thermometer in the center, so that it does not touch the glass.
4. Collect data until you have at least 5 data points around 100°C and it does not
change anymore.
5. Turn off the hotplate. Clean and organize your lab station.
6. Graph the data.
Data:
Table 1
Time (minutes)
0 min
Temperature (Co)
Create a temperature versus time graph and plot the corresponding data.
Heating Curve of Water Lab Activity
Analysis:
1.
2.
3.
4.
5.
What is temperature?
Why is the temperature going up?
Why did the temperature remain constant around 100°C and creates a plateau?
What is happening to the kinetic energy of the molecules as temperature rises?
What would happen to the kinetic energy of the molecules if the temperature would
be lowered?
6. How does this lab relate to kinetic molecular theory?
Q&A
1. What is temperature?

Temperature is a measure of the average energy of molecular motion in a substance.
2. Why is the temperature going up?
. Higher temperatures mean that the molecules are moving, vibrating and rotating with more
energy. They have higher kinetic energy.
3. Why did the temperature remain constant around 100°C and creates a plateau?

The water is boiling and the particles are changing state from liquid to a gas. Essentially the
temperature measured refers to the water (liquid state) molecules’ kinetic energy and not of
the water vapor. Energy continuous to be added but the temperature stays the same because
the water vapor’s kinetic energy is not taken into consideration.
4. What is happening to the kinetic energy of the molecules as temperature rises?

As the temperature rises molecules move much for rapidly causing the kinetic energy to rise
5. What would happen to the kinetic energy of the molecules if the temperature would be
lowered?

If the temperature is lowered the particles will move slower causing the kinetic energy to
lower.
6. How does this lab relate to kinetic molecular theory?

The particles contain kinetic energy which is increased when thermal energy is applied.
http://www.kentchemistry.com/links/Matter/HeatingCurve.htm
Heating Curve of Water Lab Activity
Essential question/Exit Slip