JCE Software, 7B1: KineticsLab

KineticsLab: The Crystal Violet/Sodium Hydroxide Reaction

John F. Cannon
Brigham Young University, Provo, UT 84602
Seven D. Gammon
University of Idaho, Moscow, ID 83843
Lynn R. Hunsberger
University of Louisville, Louisville, KY 40292

Note:
This program is out of print.

The setup for KineticsLab, showing the PSL device, "foamtronic", and computer, ready for taking samples.
KineticsLab: The Crystal Violet/Sodium Hydroxide Reaction is a computer-assisted experiment that employs IBM Personal Science Laboratory (PSL) hardware, a computer-interfaced photometer called a foamtronic, a program called KineticsLab, and the previously published Notebook program (1) to collect and analyze data for a kinetic study of the decolorization of crystal violet in basic solution. The KineticsLab program is menu driven and guides students through the data-collection process. An instructor can decide how extensive an analysis is to be done; for example, a simple study could collect room-temperature data to determine the rate law, while a more extensive study might collect data at three or four different temperatures to determine the activation energy as well.
Crystal violet (CV) is a water-soluble organic compound that contains a violet cation. Addition of sodium hydroxide converts the cation into a colorless carbinol base over a period of several minutes. The reaction is followed by measuring absorbance as a function of time, and absorbances are converted to concentrations using a calibration curve. The reaction mixture is flooded with hydroxide ion so that it is pseudo first order and a plot of ln[CV] vs time is linear. Then the rate constant can be measured at two or more concentrations of hydroxide ion to determine the order with respect to OH.
The foamtronic photometer consists of a green light-emitting diode as a light source, a photometric or radiometric probe from the PSL as a detector, and a sample compartment. Sample temperature is reported to the computer by the PSL temperature probe. All are encased in an insulating block of polystyrene foam. Directions for constructing the foamtronic are included in this issue.
Hardware and Software Requirements
Programs in Series B of JCE: Software are designed for IBM PS/2, PC, or PC-compatible microcomputers with 640K of RAM and one floppy disk drive. VGA or compatible graphics and PC- or MS-DOS 3.1 or later are also required. Disk drives with a capacity of 800 K or larger are recommended. KineticsLab also requires an IBM Personal Science Laboratory with temperature probe and photometric or radiometric probe. Additional materials are also required to build the foamtronic photometer.
Acknowledgement
Support for this project was provided by NSF Grant USE-9150265.
Literature Cited

Rittenhouse, R. Notebook: A Column Calculator, J. Chem. Educ.: Software, 1991, IV B (1).

First Published: June 1994
Citation: Cannon, J. F.; Gammon, S. D.; Hunsberger, L. R. . KineticsLab: The Crystal Violet/Sodium Hydroxide Reaction J. Chem. Educ. Software 7B1
Keywords: Laboratory; High School; General; Reaction rate; Reaction mechanisms; Initial rate method; Lab interface-PSL

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Last Updated: April 27, 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.



KineticsLab: The Crystal Violet/Sodium Hydroxide Reaction
John F. Cannon Brigham Young University, Provo, UT 84602 Seven D. Gammon University of Idaho, Moscow, ID 83843 Lynn R. Hunsberger University of Louisville, Louisville, KY 40292

Note:	This program is out of print.

The setup for KineticsLab, showing the PSL device, "foamtronic", and computer, ready for taking samples. KineticsLab: The Crystal Violet/Sodium Hydroxide Reaction is a computer-assisted experiment that employs IBM Personal Science Laboratory (PSL) hardware, a computer-interfaced photometer called a foamtronic, a program called KineticsLab, and the previously published Notebook program (1) to collect and analyze data for a kinetic study of the decolorization of crystal violet in basic solution. The KineticsLab program is menu driven and guides students through the data-collection process. An instructor can decide how extensive an analysis is to be done; for example, a simple study could collect room-temperature data to determine the rate law, while a more extensive study might collect data at three or four different temperatures to determine the activation energy as well. Crystal violet (CV) is a water-soluble organic compound that contains a violet cation. Addition of sodium hydroxide converts the cation into a colorless carbinol base over a period of several minutes. The reaction is followed by measuring absorbance as a function of time, and absorbances are converted to concentrations using a calibration curve. The reaction mixture is flooded with hydroxide ion so that it is pseudo first order and a plot of ln[CV] vs time is linear. Then the rate constant can be measured at two or more concentrations of hydroxide ion to determine the order with respect to OH. The foamtronic photometer consists of a green light-emitting diode as a light source, a photometric or radiometric probe from the PSL as a detector, and a sample compartment. Sample temperature is reported to the computer by the PSL temperature probe. All are encased in an insulating block of polystyrene foam. Directions for constructing the foamtronic are included in this issue. Hardware and Software Requirements Programs in Series B of JCE: Software are designed for IBM PS/2, PC, or PC-compatible microcomputers with 640K of RAM and one floppy disk drive. VGA or compatible graphics and PC- or MS-DOS 3.1 or later are also required. Disk drives with a capacity of 800 K or larger are recommended. KineticsLab also requires an IBM Personal Science Laboratory with temperature probe and photometric or radiometric probe. Additional materials are also required to build the foamtronic photometer. Acknowledgement Support for this project was provided by NSF Grant USE-9150265. Literature Cited Rittenhouse, R. Notebook: A Column Calculator, J. Chem. Educ.: Software, 1991, IV B (1).


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

Last Updated: April 27, 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.