Data sheets: An instructional aid

Atomic Radii: for all elements except astatine, the lantha- nides, and actinides. 8. Ionic Radrr: of 21 selected ions. 9. Lattice Energies: of 20 sele...
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Data Sheets An Instructional Aid S. G. Davis' and W. E. Harris University of Alberta. Edmonton, Alberta, Canada T6G 2G2 A comprehensive, one-page listing of the tables containing most of the data requiredfo; solving in a course can he an important educational aid to both the students and the teachers of many disciplines. Students taking a science course need to learn the types of data available and which numbers to use for a particular assignment. However, in most cases these tables of data are scattered throughout the texts, or in some cases the data mav not even be assembled in a convenient form but may be hidden in passages in the text. The search for data mav waste studv or examination time. To aid chemistry students a t the university of Alberta we have developed over the years a one- age chemistry data sheet that contains much of the data used in general, analytical, and inorganic chemistry. Presenting the data to the student on two sides of a 21- x 28-cm sheet provides a useful learning tool that allows him or her to review quickly the types of data with which he or she should be familiar and to improve his or her efficiency in obtaining these data. This sheet is an aid to the instructor in setting examinations. When it is necessary to include the pertinent data in a problem assignment, the student is given an unrealistic clue to the solution. If a data sheet is provided to which the student must refer, he or she is put in a more nearly real-life situation. Providing a data sheet thus allows the teacher in an examination to obtain a better assessment of the student's ability to solve problems. The data sheet developed here contains over 1000 pieces of information arranged in 24 tables with the following headings:

3. Solubility Product Constonts: for 36 compounds. 4. Net Stability Constants: for 24 ions. 5. First Ionization Constonts: for all elements except the lan6.

7. 8. 9. 10. 11. 12. 13. 14. 15. Iti I: 18.

19. 20. 21. 22. 23. 24.

thanides and actinides arranged into a periodic chart in electron volts. Electronegatioities: Pauling values for all elements except the inert gases, lanthanides, and actinides arranged into a periodic chart. Atomic Radii: for all elements except astatine, the lanthanides, and actinides. Ionic Radrr: of 21 selected ions. Lattice Energies: of 20 selected salts. Half Liues: 21 common isotopes are listed. Acid-Base Indicators at 25 OC: 12 are included with pH range, pKj,, and colors. Electrode Potentials, E": for 50 common half reactions. Mean Activity Coefficients:for three compounds at four eoneentratians. Data Reieetion-QTable Bond ~ntholoiesy25 bond tvoes ,. are listed. ll,,orr o i F c . r r n u r t ~ . n tur : 68 cotupound provided u,irh a cul,y OI the dntn shwr at the berinn~nwd t h r rwm, which he uses for his aisirnmenta throughout the year, and thus becomes familiar with the format of the sheet. A new sheet is handed out with each examination to pre-

Volume 64

Number 6

June 1967

525

vent the use of defaced copies. The cost of production is low enough that there is no need to have them returned after the examination. This saves time in sorting out defaced sheets and also allows the students to obtain several copies for use in several folders and books. The University of Alberta data sheet is used in several colleges and by several departments other than the chemis-

526

Journal of Chemical Education

try department. I t is also used in several commercial laboratories, is included in several locally produced laboratory manuals, and appears in one professional manual. Such reference sheets could be useful if developed for other disciplines such as physics, geology, pharmaceutical sciences, or biochemistry. Single copies of the University of Alberta data sheet are available on request.