Chemical Educcrtion: Software I
Abstract for Volume IVA, Number 1
Body Centered Cubic
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ldeal Gas Richard Hiatt Brock University St. Catharines, Ontario, Canada L2S 3A1 Ideal Gas simulates an experimental apparatus consisting of a container and piston connected to a tank of gas (hydrogen, nitrogen, or carbon dioxide). The experimenter can easily manipulate temperature, pressure, volume, and amount and composition of gas in the container (see Fig. 1). In addition the gas molecules are animated in a fairly realistic manner. They undergo elastic collisions with the sides of the container and with each other; small molecules move faster than larger ones. This animation helps students visualize the relationship between the motion of the molecules and macroscopic parameters such as temperature. Ideal Gas also allows an experimenter to collect data as system parameters are changed. These data can then be displayed as graph involving any pair of the variables: pressure, volume, temperature, amount of gas; graphs can be printed. Data can also be saved to a disk file and imported into other programs for more extensive analysis andlor inclusion in lab reports.
Crystal Lattice Dave Trapp Sequim High School Sequim,Washington 98382 Crystal Lattice is a program for the Apple 1 1 ~ sthat depicts the arrangements of atoms in four crystal lattices: simple cubic, hexagonal closest packed, cubic closest packed, andbody-centered cubic (see Fig. 2).Periodic charts highlight all elements that adopt each lattice. Animated sequences provide additional aid in visualizing eachlattice. Exploded views separate lattice layers so that the packing scheme may be more readily understood. Other animations include, for example, rotating a cubic-closest-packedlattice to help students visualize the relationship between the closest packed layers and the face-centered cubic arrangement.
Figure 1. Screen display from ldeal Gas showing gas container with piston, tank of gas, and gauges for temperature, pressure, and amount of gas.
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Journal of Chemical Education
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Figure 2. Display of body-centered cubic structure from Crystal Lattice. Crystal Lattice is a n example ofinteractive soRware that can be easily viewed by moving and clicking the Apple IIGS mouse; it consists of stacks created with HyperStudio.' An abbreviated, run-time version of HyperStudio is included so that Crystal Lattice can be used by everyone, not just those who own HyperStudio. The stacks can be modified by owners of the full HyperStudio program, using a mouse and pull-down-menu selections. An instructor or student can show any portion of the Crystal Lattice stacks in any sequence, skipping or reviewing as desired, thereby providing an effective means to learn about crystal lattices rapidly.
About This Issue John W. Moore and Jon L. Holmes, Editors University of Wisconsin-Madison Madison, WI 53706 Computer animation provides an effective way to help students visualize many molecular-scale phenomena. Visualizing the motion of ideal gas molecules and the packing of atoms in crystals are two such phenomena. Ideal Gas will be useful whenever an instructor wants students to explore the relationship among pressure, volume, temperature, amount, and composition of an ideal gas. In addition simulated motion of the gas molecules permits visualization of kinetic-molecular theory. Data can be displayed graphically to aid in understanding the relationships among P, V, T,and n for an ideal gas. Ideal Gas serves equally well in demonstration mode for the instructor to present to an entire classroom or as a tool for indeoendent student exdoration of the . ~hvsical . .ropert . ties of ideal gases. Crvstal Lattice can be used to introduce im~ortantsolidstate concepts into a course. It may be used effectivelyby an instructor to demonstrate to an entire class how atoms are packed into crystal lattices or by students individually to examine crystal structures more closely. By means of a mouse interface and button icons Crystal Lattice provides a simple way to visualize and manipulate four important crystal structures. Given the current importance of solidstate chemistry in industry and research, Crystal Lattice provides a timely addition to most instructors' toolkits. Hardware Requirements:Ideal Gas requires an Apple 10'Keefe.D.; Klimas, D.; Mueller, E. HyperStudio; Roger Wagner: El Cajon. CA.
IIe, IIc, or 11- computer with a t least one disk drive. Apple IIe computers must have a t least 128K RAM and the capability of displaying 80-column text. Ideal Gas runs under the ProDOS2 operatinp system. Printinpmaphs - - . from w~thinldealGasrrq"iresan~ppleImageWriwrorcompntihle orinter. C ~ s t a Lattice l rruuires an Aoole llcs with at leas; 1.25 MB &and one 3.5fin. 8 0 0 ~ ~ drive { ~ krunning ZProDOS, Apple Computer, Inc., Cupertino, CA. 3GS/OS, Apple Computer, Inc., Cupertino, CA. 4Susskind,T. Y. J. Chem. Educ.: Software 1988, 1A(1), 16-24.
under GS/OS3 version 5.02 or higher. A color monitor is highly recommended. Asecond 3.5-in. 800K disk drive or a hard disk is desirable. For classroom presentation of either Ideal Gas or Crvstal Lattire a large screen tclev~sionmomtor or overheadprojcction pmcl is appropriate;' Vidrn output l'rom a n Apole II or IIGS compute; may be sent to a large-screen dispiay using a standard RCA cable. This provides a powerful method of presenting information that complements lecture, chalkboard, overhead projector, demonstration, and film or video tape.
Volume 68 Number 5
May 1991
409
