JCE Software, 2B2: The Acid Base Package

The Acid Base Package: A Collection of Useful Programs for Proton-Transfer Systems

Richard W. Ramette
Carleton College, Northfield, MN 55057

Note:
This program is out of print.

The Acid-Base Package consists of four programs that deal with the types of acid-base calculations normally encountered in introductory and analytical chemistry courses. It also includes three utilities that complement the calculation programs.
FABTIC, the Final Acid-Base Titration Curve program, calculates theoretical titration curve data for any mixture of acids and/or bases, using strong acid or strong base as titrant. A disk file, ACIDBASE.LIB, contains 126 molecular substances with their pK values, molecular weights, and formulas, from which the user can choose. Initial volume and concentrations, titrant concentration, pH range to be included, precision of the data, and whether to include the effect of ionic strength on activity coefficients may be set by the user. Calculated data may be printed and/or saved in a library disk file.
ALPHA plots species distribution curves for proton-transfer systems and for metal-ligand systems. Each species in the system will have a curve showing the fraction of the total that it represents as a function of pH (or as a function of ligand concentration for metal-ligand systems). Plots may be made with either linear or logarithmic representation. Like FABTIC, ALPHA gets pK data from ACIDBASE.LIB.
BUFFPREP offers guidance for the preparation of pH buffers. The user specifies the substance (e.g., citric acid or ethylenediamine), the desired pH, ionic strength, and volume, and the program indicates quantity of the substance to be used along with the calculated amount of strong acid or strong base required to achieve the desired pH. In a second mode, BUFFPREP can search ACIDBASE.LIB for all substances technically suitable for preparing a buffer of a specified pH, and then the user can make a choice.
PHCAL is perhaps the most useful for the myriad pH calculations taught to high school students and undergraduates. It deals with the seven fundamental types of solutions: neutral solute, strong acid, strong base, weak acid, weak base, buffer, and ampholyte. The user specifies pK values, concentrations, and whether to include ionic strength effects, and the program produces the pH and other related quantities at equilibrium.
CURVPLOT is a general purpose plotting program that conveniently plots titration curves calculated by FABTIC. It can also plot any other X-Y data no matter what the range of X and Y values. Up to 10 data sets may be plotted at once, and each may be represented as a smooth curve, as small points, or as large points. The user has complete control over axis scaling and labeling. Any data set may be plotted together with its first derivative and/or inverse derivative. A useful feature of CURVPLOT is the use of "cross hairs" to read the X, Y coordinates at any point on the plot. They may also be used to mark any region of the plot for expansion, which is valuable for precise endpoint evaluation.
XYFILE is a utility that makes it easy to prepare data files for plotting by CURVPLOT. It provides options for adding, deleting, or changing data points in existing files and for printing a file.
SEARCH is a program that can search ACIDBASE.LIB for substances that meet a combination of specifications provided by the user. For example, it will find all diprotic acids that are in a certain range of molecular weights and also have one of their pK values in a certain range. it will find all acids containing a certain element, or all acid-base indicators with the centers of their color change intervals in a certain pH range. It also makes it easy to make additions to the library file.
The Acid-Base Package comes with full documentation of these programs, as well as discussion of fundamental principles of titration curve calculations, the importance of ionic strength, suggested laboratory experiments, and examples of assigned exercises.

Screen from The Acid-Base Package.
Hardware and Software Requirements
The Acid-Base Package runs under MS-DOS or IBM PC DOS version 3.0 or higher. It is supplied on 5.25-in. disks but can be used on a computer with either two 5.25-in. disk drives or two 3.5-in. disk drives or on a computer with a hard disk. At least 512K RAM is required. ALPHA and CURVPLOT require a graphics adapter (CGA, EGA or VGA). The program detects the type of graphics adapter available and utilized the highest possible resolution. In some cases one may wish to have a graphics printer to print titration curves or species distribution plots, but all programs will run without a printer.
Literature Cited

Susskind, T. Y. J. Chem. Educ.: Soft. 1988, 1A(1), 16-24.

First Published: October 1989
Citation: Ramette, R. W. . The Acid Base Package: A Collection of Useful Programs for Proton-Transfer Systems J. Chem. Educ. Software 2B2
Keywords: Lecture Aid; Computer Room; Simulation; High School; General; Analytical; Titration curves; Buffers; pH; Alpha plots

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Last Updated: April 26, 2001
Created: December 3, 1996 Created by: J. L. Holmes
Comments to: jceonline@chem.wisc.edu

© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.



The Acid Base Package: A Collection of Useful Programs for Proton-Transfer Systems
Richard W. Ramette Carleton College, Northfield, MN 55057

Note:	This program is out of print.

The Acid-Base Package consists of four programs that deal with the types of acid-base calculations normally encountered in introductory and analytical chemistry courses. It also includes three utilities that complement the calculation programs. FABTIC, the Final Acid-Base Titration Curve program, calculates theoretical titration curve data for any mixture of acids and/or bases, using strong acid or strong base as titrant. A disk file, ACIDBASE.LIB, contains 126 molecular substances with their pK values, molecular weights, and formulas, from which the user can choose. Initial volume and concentrations, titrant concentration, pH range to be included, precision of the data, and whether to include the effect of ionic strength on activity coefficients may be set by the user. Calculated data may be printed and/or saved in a library disk file. ALPHA plots species distribution curves for proton-transfer systems and for metal-ligand systems. Each species in the system will have a curve showing the fraction of the total that it represents as a function of pH (or as a function of ligand concentration for metal-ligand systems). Plots may be made with either linear or logarithmic representation. Like FABTIC, ALPHA gets pK data from ACIDBASE.LIB. BUFFPREP offers guidance for the preparation of pH buffers. The user specifies the substance (e.g., citric acid or ethylenediamine), the desired pH, ionic strength, and volume, and the program indicates quantity of the substance to be used along with the calculated amount of strong acid or strong base required to achieve the desired pH. In a second mode, BUFFPREP can search ACIDBASE.LIB for all substances technically suitable for preparing a buffer of a specified pH, and then the user can make a choice. PHCAL is perhaps the most useful for the myriad pH calculations taught to high school students and undergraduates. It deals with the seven fundamental types of solutions: neutral solute, strong acid, strong base, weak acid, weak base, buffer, and ampholyte. The user specifies pK values, concentrations, and whether to include ionic strength effects, and the program produces the pH and other related quantities at equilibrium. CURVPLOT is a general purpose plotting program that conveniently plots titration curves calculated by FABTIC. It can also plot any other X-Y data no matter what the range of X and Y values. Up to 10 data sets may be plotted at once, and each may be represented as a smooth curve, as small points, or as large points. The user has complete control over axis scaling and labeling. Any data set may be plotted together with its first derivative and/or inverse derivative. A useful feature of CURVPLOT is the use of "cross hairs" to read the X, Y coordinates at any point on the plot. They may also be used to mark any region of the plot for expansion, which is valuable for precise endpoint evaluation. XYFILE is a utility that makes it easy to prepare data files for plotting by CURVPLOT. It provides options for adding, deleting, or changing data points in existing files and for printing a file. SEARCH is a program that can search ACIDBASE.LIB for substances that meet a combination of specifications provided by the user. For example, it will find all diprotic acids that are in a certain range of molecular weights and also have one of their pK values in a certain range. it will find all acids containing a certain element, or all acid-base indicators with the centers of their color change intervals in a certain pH range. It also makes it easy to make additions to the library file. The Acid-Base Package comes with full documentation of these programs, as well as discussion of fundamental principles of titration curve calculations, the importance of ionic strength, suggested laboratory experiments, and examples of assigned exercises. Screen from The Acid-Base Package. Hardware and Software Requirements The Acid-Base Package runs under MS-DOS or IBM PC DOS version 3.0 or higher. It is supplied on 5.25-in. disks but can be used on a computer with either two 5.25-in. disk drives or two 3.5-in. disk drives or on a computer with a hard disk. At least 512K RAM is required. ALPHA and CURVPLOT require a graphics adapter (CGA, EGA or VGA). The program detects the type of graphics adapter available and utilized the highest possible resolution. In some cases one may wish to have a graphics printer to print titration curves or species distribution plots, but all programs will run without a printer. Literature Cited Susskind, T. Y. J. Chem. Educ.: Soft. 1988, 1A(1), 16-24.


News \| Issues \| CD-ROM / Video \| Find It! \| Technical Support \| For Authors
JCE Online \| Journal \| Software \| Internet \| Happenings \| About JCE \| Contact JCE

Last Updated: April 26, 2001 Created: December 3, 1996	Created by: J. L. Holmes Comments to: jceonline@chem.wisc.edu

© 1997 Division of Chemical Education, Inc., American Chemical Society. All rights reserved.