computer mrie~.76 Most authors of Bits and Pieces will make available listings and/or machine-readable versions of their programs. Please read each description carefully to determine compatibility with your own computing environment before requesting materials from any of the authors. Guidelines for Authors of Bits and Pieces appeared in July 1986. Several programs described in this article and marked as such are available from Project SERAPHIM. Disks are available a t $5 per 5%-in. disk, $10 per 3'/2-in. disk; program listings and other written materials are available for $2 each; $2 domestic or $10 foreign postage and handling is required for each shipment. Make checks payable to Project SERAPHIM. T o order, or get a Project SERAPHIM Catalog, write to: John W. Moore, Director, Project SERAPHIM, Department of Chemistry, Eastern Michigan University, Ypsilanti, MI 48197.
The Periodic Table as a Data Base
edited by JOHN W. MOORE Eastern Michigan Universily. Ypsilanti. MI 48197
programs are particularly useful instructional tools for teaching the periodic table and has written such a program for the Apple I1 family of computers. The data hase is a collection of information about the chemical and physical properties of the elements. I t is managed by examining the entries to see if certain criteria are met. For example, one might wish to see a list of all elements with melting points less than 273 K, a list of those with three p valence electrons, or a list of those elements with alphaemitting isotopes whose lifetimes are greater than one year. The results of these inquiries are displayed in the form of a periodic tahle. In this program, an element's information is obtained by moving a cursor over the symbol of the element (Fig. 1). Alternatively, the student may have the program search for
IR
ELEMENT NAMES
UIII
George W. Goth
Skyline College San Bruno, CA 94066 Introductory chemistry courses generally devote a week or more to the study of periodicity and the periodic table. However, it is often difficult for beeinnine students t o erasn - . the full utility of the concept of p&iodiciiy. First, thr amount of data isvast and it is usuallv oresented in table form or in traditional two dimensional iine graphs. In both cases, the periodic behavior may belost in the details of the data. How is a beginning student t o see the "forest" of periodicity among the "trees" of 103 electron configurations arranged in a table? Second, the concepts are sophisticated, and i t is difficult for beginning students t o grasp, simultaneously, their meanings as well as their relationships to the periodic tahle. A graph of molar volume versus atomic number does show a series of bumps and is said t o illustrate periodic behavior. But many students have considerable difficulty relating this graphical information t o the structure of the periodic tahle. With the advent of microcomputers it is possible to teach concepts such as periodicity in ways that are not only more accessible t o the student but dynamic and interactive as well. The author believes graphical data hase management
836
Journal of Chemical Education
LANTHANIDES Ce p r l ~ pml~m d E U ~ Tb G ~DY~HOEr Tm Yb Lu ACTINIDES ~hPal U N ~ ~ APmUl ~ r n~k Cf ~ m NO~Lr d
IES
Ir: iridium CL. rainbow1 F QUTB 1. An element m y oe selected by using the K, H. U, and M keys to move Ihe cdrsor arouna me periodic table. Here informatbn about the name of tne e ement lr is dosplayea, and me element's pos lion in the perimic table is highlighted.
all elements meetine certain requirements (Figs. 2 and 3), while another option allows the student to create a pseudothree-dimensional display . . of a chemical or physical property (Fig. 4). The disk has data files containing the names, atomic masses, atomic numbers, melting points, boiling points, molar volumes, specific heats, electron configurations, covalent radii, first ionization potentials, electron affinities, electronegativities, terrestrial and solar abundances, states under standard conditions, metallic classifications, common oxidation states, year of discovery, longest-lived radioisotopes, and derivation of names of the elements. Also included are utilities for adding, editing, updating, removing, listing, and combining the data base sets and a complete tutorial on how to operate the program and its utilities. The disk and documentation are available for $15 from the author a t the above address or from Project SERAPHIM.
BOILING POINT
n UIII
individuaiizd Exercises in information Retrfievai for High Enrollment Courses: Use of the CRC Handbook J. Dlehl and D. Onwood
Indiana-Purdue University Fort Wayne, IN 46805 Recent changes in our course structure included the abandonment of a one-semester-credit-hour formal course in chemical literature in favor of integrating that material throughout the undergraduate curriculum. We begin in the first year with the use of handbooks such as the CRC "Handbook of Chemistry and Physics". While the department had always encouraged students to consult this resource in the freshman laboratory, such use tended t o be limited; i t provided little awareness of how the material was arranged or how i t could he used for situations beyond the immediate need. Since the skills to be mastered are best acquired by performing related tasks, we considered methods by which this might be done effectively in relatively high-enrollment groups. We wished t o encourage peer assistance, while ensuring that this assistance was directed toward fulfilling the object of the exercise. We have developed and implemented a procedure that provides each student with a sliahtly different exercise for ;he handbook as a whole. Each ex-ercise consists of a series of items that involve the retrieval from the handbook of a piece of information in a topic area that is mentioned in our firstyear course. Most items differ from student to student in their specifics. We have chosen to arrange them in the sequence in which they will be found in the reference source in order to give a "self-guided tour". The exercises are produced using a personal computer and printer. A BASIC source code contains the text of each question less a crucial blank. The blank is filled by selecting the comnuter from a set of alterna~ - - "random" -~ - function -~ ~ ~ of ~ the ~ ~ tives stored in disk files. This is repeated for other questions; the deeree of commonalitv between any two students is thus very low. The program assigns a unique number to each exercise during a given production run and stores the selections. The paper may bear an identifier chosen by the in-
-
Fioure criteria can be displayed. The studem . . "~ 2. Elements meellno " soecitied . may select a pamcular v a l a , an upper or lower iimll, n a range tor the dam. Alternalivdy. h e prqram ulli s w t the oata nta a series of 'oms" snddlsp ay m e m w h s ~eq~entialiy Here me elemenls with o m lng points oetween 0 and 273 K are shown. ~
Ifi
BOILING POINT ELECTRON CONFIGURATIONS
Ulll
LANTHANIDES ~ e ~ P r l ~ d l ~ r n l ~ m l ~ $ d l ~ b l ~ y l ~ o ~ ~ r l ~ m l ~ b ~ l u l &I~rn(tIdl~ol~r ACTINIDES ~ h l ~Ua(~p(~ulArnl~rnl%kl~f Figure 3. n Is passibie to display data meeting alphanumeric crileria as well. Here the elements with w e e p electrons are highlighted.
Flgure 4. Pseudc-lhree-dimensional displays of the data set are posdbie. Here me elements with higher boiling points are displaced to me upper right. The display was drawn live in under a minute.
Volume 63 Number 10 October 1986
837
