can be merged and the redistribution of energy within the new combined system observed. Normallv enerm is exchanged completels randomly, b k it ispossible toimpose constraints, such as exchange - only between neighbors. The program provides'a variety i f ways to demonstrate that although the individual, microscopic components of the system are behaving randomly, the macroscopic system itself can exhibit orderly and predictable behavior.
About This lssue John W. Moore Jon L. Holmes University of Wiswnsin--Madison Madison, WI 53706
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The three Droerams in this issue are applicable over a broad range of educational ievels. Lake Studv for Windows is derived from a program designed for a college-level course for nonScreen from Lake Study program showing simulated fish-tank experiment. science maiors. " . but its precursor has been used successfully in middle schools and with honors simulated colleague about what they have found. Having students a t the freshman level. Atomic Spectroscopy is done this students can develop a hypothesis about the suitable for courses ran&ng from introductory high school prohlrm: however, there are randoml~chosendilTerences or college level throughad;;anced undergraduate phyalcal In the information provided that lead some students to a and inorganic chemistry. Microstate wdl be useful in any diff'erent hypothesis from others. In the secund part of the situation where an instructor wants to make the ideas of simulation students can do contmllcd experiments to destatistical thermodynamics more concrete. termine which of the two hypotheses is more likely. The HardwarelSofware Required fact that different students reach different initial hypotheses is a good mechanism for inducing classroom discusThis issue of JCE: Software is designed to run on IBMsions about the facts that support each hypothesis and PC, PSl2, or MS-DOS compatible computers with a t least their logical interpretation. Student handout guides are 640K RAM and one disk drive, except where noted below. provided for each of the two parts of the simulation. A printer is not required but will be useful in many cases to make copies of data or graphs. The software is supplied on both 5.25-in. and 3.5-in. disks. Microstate The Atomic Spectroscopy and Microstate programs require a Color Graphics Adapter (CGA) or compatible Richard York graphics, and a color monitor is recommended. DOS verWittenberg University sion 2.1 or later is also required and is not supplied with Springfield, OH 45501 the programs. Lake Study for Windows is designed to run on a n IBM or Microstate allows experimentation with a simulated compatible computer built upon a n 80286 or higher microC W S that ~ ~ is viewed as a set of loosely coupled harmonic processor. Greater than 1MByte of RAM, a hard disk, and oskllators. Energy is exchanged randomly among pairs of one floppy-disk drive are also required. A CGA, EGA, VGA, oscillators and the computer tallies energy states and dis8514, Hercules, or compatible display is required. (EGAor plays a bar graph showing average occupancies of the first higher resolution and a color monitor are recommended.) A fifteen energy levels. This graphically demonstrates the mouse is not required, but is highly recommended to take development of the Boltzmam distribution of energies a s advantage of the graphical interface. DOS version 3.1 or the equilibrium state of a n unconstrained system. Micmgreater and Windows version 3.0 or greater are required state does not use Boltzmann's theory to calculate occuand are not supplied with the program. pancies, but rather tallies the distribution a s random ene r w exchanees take dace. I t is also possible to compare Literature Cited two systems, stopping either a t any time and allowing the other to continue to advance toward equilibrium. Two systems a t equilibrium, for example a hoione and a cold one, ~
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To Purchoro This lssue of ICE: Softwow... The issue of JCE: Software abstracted above will be shipped to all subscribers to Series B in 1992.To order a subscription at the special pre-publication price of $15 ($85 foreign)send in the insert card in this issue before April 1,1992.After that date, subscriptions will be available for $100 ($120foreign). Address all inquiries to: JCE: Software, Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, WI 53706.
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Journal of Chemical Education
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