JOURNRL OF
Chemical Education: Software Abstracts for Volume SA, Number 1 Orbital Transitions Michael Liebl Mount Michael Benedictine High School Elkhorn, NE 68022
"Orbital Transitions" displays two-dimensional plots of the chaneine electron orobabilitv densitv function in the hydrogen atom as an electron moves from one orbital to another. Each orbital of the hydrogen atom has a different electron probability density function (electroniccharge distribution). This distribution must change in a finite time interval when the electron changes orbitals. The charge distribution is accelerated during the transition resulting in the emission or absorption of a photon. The program animates this process in 25 frames for a two dimensional v-z cross section of the hydrogen atom. Three types ofplotsire used to visualize the changing charge distribution-a surface plot, a contour plot, and a dot density plot. The plots may be viewed singly or simultaneously. Any transition between states ranging from the 1s statethrough the 4f state is included. (Because of the conservation of angular momentum. not all of these transitions are allowed in nature.) The program is menu driven and comes on two DOS 3.3 disks.
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Elements and Symbols Ronald R. Pauline Gannon University Erie. PA 16505
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"Elements and Symbols" is a program designed for students in introductory high school chemistry courses or junior high or senior high school physical science courses. Before students can proceed with more advamced chemistry topics such as naming and identifying compounds,
A riame trom 'UrDltal I rans~tons~owng me cnange in cnarge alstrlbution during the 1 s + 2p transition.
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Journal of Chemical Education
chemical equations, and stoichiometry, they must be well versed in the names of the elements and their symbols. This program is basically a tutoriaWdril1and practice program that enables the student to review material on element names and symbols. It is especially useful for the student who is having trouble learning and remembering these names and symbols because it covers all the common elements and gives immediate and individual feedback on correct and incorrect responses. The student can proceed a t any pace and rerun the program a s many times as needed.
About This Issue John W. Moore Jon L. Holrnes University of Wisconsin-Madison Madison, WI 53706
This issue of JCE: Software for the Apple I1 contains two programs from opposite ends of the chemistry spectrum. "Elements and Symbols" is designed for introductory high school chemistry courses and junior high and high school physical science courses. As its name implies, it teaches students the procedures and rules used in deriving the chemical symbols of common elements. The unique aspect of this program is not so much its content but the fact that it was developed using Tutor Tech, a hypermedia environment for authoring and oresentine multimedia nresentations on the computer. Tut& ~ e c makes'it h easy to develoo such resenta at ions without knowledw of traditronal programming tcclmiques. At the other end of the sDcctrum is "Orbital Transitions". Orbital transitions occur when an electron in an atom absorbs a photon and thereby gains energy or emits a photon and loses energy. As the electron does so, it transcends from its original atomic orbital to a new atomic orbital. "Orbital Transitions" depicts this transition graphically and animates the transition a s it occurs (in simulated time, of course). The animation can be viewed as a surface plot, a contour plot, a dot density diagram, or all three simultaneously. The simultaneous viewing can be very instructive as to the relation among these three types of plots. Needless to say the chemistry here is of amuch more advanced nature than is relating element names to symbols. "Orbital Transitions" does an excellent job of depicting this advanced chemistry topic. Hardware Requirements "Orbital Transitions" requires an Apple I1 with at least 64K RAM with one 5.25-in. disk drive. A second 5.25-in. disk drive is highly recommended. "Elements and Symbols" requires an an Apple IIe with at least 128K RAM, an Apple IIc, or an Apple IIGSwith a t least one 5.25-in. disk drive. A printer is required to output student results. A mouse is supported and is recommended.
