Wednesday, March 19, 2008 - 4B

Students did the Heating and Cooling of an Unknown Substance Lab.

Homework: Graph data. On graph also show the process (boiling, freezing, melting, heating, cooling) for each segment and the phases that exist for each segment. Indicate the freezing and melting temperature by looking at the plateaus in the graph.

On the back of the graph paper, write down observations:
1. At what temperature of the substance does it first begin to melt?
2. At what temperature of the substance does it first begin to freeze?
3. When it does begin to freeze, does it freeze from the top down or from the bottom up?