Acid-Base Calculations with a Flowchart of pValues

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 13 Issue 4 (2008) pp 207-209

Acid-Base Calculations with a Flowchart of pValues

Pablo A. Molina

Chemistry Department, Murray State University, KY 42071, pablo.molina@murraystate.edu
Received February 5, 2008. Accepted July 16, 2008.

Published online: 21 July 2008

Abstract. Acid/base calculations are a particularly difficult subject for students enrolled in general, organic and biological chemistry (GOB) courses. Yet, a sound conceptual grasp of this topic is essential to understanding the chemistry of many organic and biological compounds. This paper presents a flowchart to solve acid/base calculations in the context of GOB courses. Acid-base concentrations as well as any other quantity, X, are expressed in terms of pValues(i.e., pX = – log X). Using the flowchart provided, students can solve all common pH problems following a top-down sequence of questions that leads to the appropriate equation. The use of calculators is made unnecessary by an accompanying and user-friendly logarithm plot.

Key Words: In the Classroom; general chemistry, acids and bases, students in the health sciences and related fields, acid/base calculations

(*) Corresponding author. (E-mail: pablo.molina@murraystate.edu)

Article in PDF format (99 KB) HTML format