JOURNRL OF
Chemical € ducation: Software The Periodic Table CD Alton J. Banks North Carolina State University Raleigh, NC 27695-8204 Jon L. Holmes Jn versdy of W scons n-Maatson Madlson. W 53706-1396
The Periodic Table CD is a digitized version of our alltime favorite publication, The Periodic Table Videodisc ( I ). On a single CD-ROM that can be used by both Macintosh and Windows computers i t contains a database of visual information-still images and motion sequences-about the chemical elements. The motion sequences show reactions (if any) of each element with air, water, acids, and base; the still pictures show most of the elements a s well as common and not-so-common uses and applications of each element. The CD contains files for still images and motion sequences organized by element. Within the folders (subdirectories) for most elements there are four files showing still images of the element i n its stable form a t room temperatweand normal atmospheric pressure. There are two close-ups, one labeled with the element's name and svmbol, and one unlabeled. This makes i t possible to ask students to identify a n element based on its visible characteristics. The other two files a r e medium shots (one labeled, one unlabeled) that give perspective on the size of each sample.
Table CD. long the reaction actually took. To provide a feeling for reaction rates, slower reactions are afforded more time than faster ones but not in direct proportion to the actual time required. Uses and applications of the elements comprise the third major type of information on the CD. Files containing still images that show u p to a dozen applications for each element a r e included. For each application there is a text frame that indicates what the application is and in which form (pure element, oxide, etc.) the element i s used. This is followed by a picture of one or more items i n which the element i s found. These have been made into a slide-show for each element. A movie player is included in this issue so that the still images, motion video sequences, and slide shows can be played back on both Macintosh and Windows computers. The media player can be used to edit motion video sequences-for example, to remove labels from the begiuning of a sequence that shows a reaction, so that students can be asked to identify a n element or reaction as part of a quiz or examination.
About This Issue: The Periodic Table CD Figure 1. Digitized image of aluminum from The Periodic Table CD.
John W. Moore, Editor Jn vers ly of W~sconsn-Mad son Maason. Wi 53706
Additional files in a n element's folder contain motion video sequences of u p to half a minute or so that show the element reacting with air, water, aqueous acids (6 M and 12 M HC1; 6 M and 15 M HNOB),and aqueous base (6 M NaOH). Such movie files are available for nearly every case in which a reaction is known to occur. Each begins with a label that identifies the element being reacted, and each type of reaction (with water, with acids, etc.) can be identified because the experimental set-up i s always the same. This facilitates comparisons among reactions of different elements with the same reagent, and such comparisons can be made easily, within seconds, a s a consequence of the CD-ROM player's ability to find any sequence rapidly. When a reaction is slow enough that more than 30 s would be required to follow i t to completion, the CD contains the beginning and end as well as a n indication of how
This special issue of JCE: Software is part of a n effort that originated with Project SERAPHIM to provide a n alternative a ~ o r o a c ht h a t would enhance teachine of descriptive chemistry. The original Periodic Table ~ildeodisc, on which this CD is based, was conceived as a database of visual information about applications, properties, and chemical reactivity of the elements. The CD provides a broad range of reactions and is ideally suited to those of us who want to show students as much as possible about the chemistry of the elements. The chemistry is readily available, even if we do not have samples of every element. The CD-ROM medium obviates concerns that normally accompany presentation of descriptive chemistry: safety, costs of materials, disposal of reaction products, time for preparation and clean-up, and visibility of the presentation to all members of the class. Volume 72 Number 5 May 1995
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