Heating Curve LabName:

Lab Table:

Safety:

You must wear goggles at ALL times during this lab.

Hot glassware looks just like cool glassware

Directions:

  1. Fill a 400 mL beaker with ice. Add just enough tap water to cover the ice.
  1. Place the beaker onto the hot plate.
  1. Suspend the thermometer as deep in the ice water as possible without the bulb touching the bottom or sides.
  1. Turn the hot plate onto high.
  2. Record the beginning temperature of the ice water at 0 minutes.
  1. Read and record the temperature after each minute into the data table provided.
  1. When the water has been boiling

for 5 minutes, you may stop recording and turn off the hot plate.

  1. Allow the beaker and water to cool in place.

Data:

Time / Temperature / Time / Temperature / Time / Temperature / Time / Temperature
0 min / 7 min / 14 min / 21 min
1 min / 8 min / 15 min / 22 min
2 min / 9 min / 16 min / 23 min
3 min / 10 min / 17 min / 24 min
4 min / 11 min / 18 min / 25 min
5 min / 12 min / 19 min / 26 min
6 min / 13 min / 20 min / 27 min

Graph your data on the given graph paper. Make sure you attach it to this paper to turn in.

Label your heating curve graph correctly. Make sure your graph has a title, and both axes are labeled including units.Use the WHOLE graph paper to graph your data!!!

Label these parts on your graph:

  1. Ice (Solid)
  2. Melting point
  3. Liquid water
  4. Boiling point
  5. Gas

Conclusions:

1. What temperature did your ice melt at? Explain how you know.

2. What temperature did your water boil at? Explain how you know.

  1. Were the phase changes you observed today exothermic or endothermic and why?
  1. If you were adding thermal energy the whole time, why did you have periods where your temperature did not change much? (What was the thermal energy doing during those time periods?)

Heating Curve of Lauric Acid
90
80
5. Look at this graph of a waxy material / Celsius)
calledLauric Acid. At what temperature / 70
does Lauric acid change from a solid to a / 60
liquid? ______Describe why / (degrees / 50
you chose this temperature from the
graph. / Temperature / 40
30
20
10
0
0 / 5 / 10 / 15 / 20 / 25 / 30
Heating Time (minutes)