Peter Torpie                                                                                                                            Return to Physics Menu

New Milford High School, New Jersey

Summer 2001

Melting and Boiling Points
or
How much junk food can I smuggle past the teacher by calling it science?

Object: to familiarize the students with the techniques of measuring melting and boiling points of various substances. It is a good introduction to the safe 
use of heat sources in the classroom, as well as teaching how to read an alcohol thermometer.

Materials: 

• heat source (alcohol lamp, Bunsen burner, hot plate)
• electric and glass thermometers
• tongs
• ring stands
• containers (soup cans work great for this
  experiment)
• substances supplied by the student.

Setup: working in groups of four or five, each group must devise a way to find the melting and boiling points of 6 substances, to be provided by the students. 
These substances must not have boiling or melting points that exceed the capacity of the thermometers. Each group is also responsible for cleaning up any mess they 
might make.

Warning to teachers: this experiment involves heat sources, which can be dangerous. It will also take about 20 seconds for the students to realize that they can use ice cream and soft candy as subjects for experimentation (hard candy burns without melting). Your classroom will very quickly resemble an ice cream parlor as students use one scoop for melting and the rest for eating. It is surprising what students will eat at 9:00 in the morning. Trying to teach about controlling variables when students are eating banana splits can be extremely trying. The best you can do is to make sure they all use the same flavor, with different brands or different fat content. 

Teaching Standards: B, C, D and E

Content Standards: A, D, E and G