Chemical Education Today
Reports from Other Journals
The Physics Teacher by Volker B. E. Thomsen Two recent articles in this journal dedicated to introductory physics education should be of interest to teachers of introductory chemistry, especially high-school teachers. “Class Simulation of Thermal Energy and Heat” by James Jadrich and Stanley L. Haan (TPT, 1999, 37, 98–99) describes a fun-filled learning activity in which the students play the roles of molecules in whole-class simulations of various aspects of thermal energy. Each student is given an equal number of marbles, representing kinetic energy units, which are then exchanged with others using the “rock, paper, scissors” game. To simulate a solid, students may only interact with their neighbors and, after a short time, it can be seen that the marbles become randomly distributed throughout the room. Conduction in a solid is simulated by the instructor introducing additional marbles at one side of the room. Now the marble distribution will show a decrease from the “hot” (instructor) side. For a liquid, the students may walk about but not be more than an arm’s length from the rest of the group. In the simulation of evaporation, students may leave the class (evaporate) upon obtaining six marbles. However, half of the marbles must be given to the instructor, representing the latent heat. A gas can be simulated by allowing
the students to move freely about the room while exchanging marbles. Additional simulation ideas and tips for the instructor are found in the article. In “Golden Oldies: Black Sack Atoms” by Kevin Pennington (TPT, 1999, 37, 176), the author provides an interesting variation of the “black box” exercise; this one is designed to help students gain a better sense of the reality of atoms. One of the most common complaints heard at all levels of science instruction is: “If they’re too small to be seen, then how do we know they really exist?” This fun learning exercise can be used to pave the way for a discussion of how science probes the unseeable. Basically, the instructor places a variety of different objects in opaque bags and challenges the class to discover the contents. Rules regarding what may and may not be done or used in this process must also be provided. Looking into the bag, putting fingers into it, or tearing the bag are not allowed. However, typical introductory laboratory apparatus such as scales and rulers are acceptable. Further tips and suggestions are provided in this note. Volker Thomsen is an applications scientist at Spectro Analytical Instruments, Inc., 160 Authority Dr., Fitchburg, MA 01420; email:
[email protected].
JChemEd.chem.wisc.edu • Vol. 76 No. 8 August 1999 • Journal of Chemical Education
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