Literaturnachweis - Detailanzeige
| Autor/inn/en | Pergantis, Spiros A.; Saridakis, Lakovos; Lyratzakis, Alexandros; Mavroudakis, Leonidas; Montagnon, Tamsyn |
|---|---|
| Titel | Buffer Squares: A Graphical Approach for the Determination of Buffer pH Using Logarithmic Concentration Diagrams |
| Quelle | In: Journal of Chemical Education, 96 (2019) 5, S.936-943 (8 Seiten)Infoseite zur Zeitschrift
PDF als Volltext |
| Sprache | englisch |
| Dokumenttyp | gedruckt; online; Zeitschriftenaufsatz |
| ISSN | 0021-9584 |
| DOI | 10.1021/acs.jchemed.8b00588 |
| Schlagwörter | Leitfaden; Unterricht; Lehrer; Visual Aids; Chemistry; Scientific Concepts; Concept Teaching; Science Instruction; Secondary School Science; College Science; Equations (Mathematics) |
| Abstract | Teaching the concept of pH buffers is considered to be important both in the final high-school years and at the early undergraduate level. Here, we propose the use of pH-log C diagrams to investigate the properties of pH buffers. This graphical approach is extremely simple to employ because it only requires drawing a simple square that can then be used to determine relevant pH-buffer parameters. This square is based on the Henderson-Hasselbalch equation with the length of each of its sides equal to abs(pH-pK[subscript a]) and abs(log C[subscript b]-log C[subscript a]). In addition, the "buffer square", as we propose naming it, can be used by instructors as a pedagogical tool to introduce the concept of buffer capacity, to help determine pH change upon the addition of an acid or base, and to easily calculate the required concentrations for preparing a pH buffer with specific properties. Finally, we consider this approach to be especially powerful for helping students visualize the location of a buffer system on a full pH-log C diagram and, thus, help them evaluate if the Henderson-Hasselbalch equation is valid for accurate pH determination as an alternative to the more complex cubic or quadratic equations that are needed to describe acid--base equilibria more precisely in some cases. (As Provided). |
| Anmerkungen | Division of Chemical Education, Inc. and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: eic@jce.acs.org; Web site: http://pubs.acs.org/jchemeduc |
| Erfasst von | ERIC (Education Resources Information Center), Washington, DC |
| Update | 2020/1/01 |
Literaturbeschaffung und Bestandsnachweise in Bibliotheken prüfen
Permalink als QR-Code
Inhalt auf sozialen Plattformen teilen (nur vorhanden, wenn Javascript eingeschaltet ist)
Teile diese Seite:
