JCE Online Journal of Chemical Education
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print
   Current Issue
 Previous Issues
 Supplements
 Search JCE Index

JCE Digital Library
   DigiDemos
 QBank
 SymMath
 WebWare

JCE Software
   Latest Releases
 Software & Video
 Downloads
 Support

Only@JCE Online
   JCE Online Store
 JCE HS CLIC
 JCE Discussion Forums
   Biographical Snapshots
 ChemEd Resource Shelf
 Featured Molecules
 Hal's Picks
 Project Chemlab
 Reviewed WWW Sites
 "Web-Ed" Articles

About JCE
   Features
 Publications
 Operations
 Outreach
 Contact Us


  Home > JCE Print > Journal of Chemical Education > Issues > 2001  > November  >
In the Laboratory
The Measurement of Activity Coefficients in Concentrated Electrolyte Solutions. An Experiment for the Physical Chemistry Laboratory
Judith M. Bonicamp, Ashley Loflin, and Roy W. Clark
Department of Chemistry, Middle Tennesesee State University, Murfreesboro, TN 37132
Cover
November 2001
Vol. 78 No. 11
p. 1541
Abstract
A physical chemistry experiment is described in which a relatively inexpensive osmometer is used to measure the practical osmotic coefficient of 1:1 strong electrolyte solutions. These data can be used to calculate mean ionic activity coefficients using nonlinear curve fitting and some instructive spreadsheet calculations. Because of data smoothing via the curve fit, the results are a surprisingly satisfactory way for students to measure activity coefficients in the course of a 3-hour laboratory. Student-determined values of the mean ionic activity coefficient are within 4% of literature values for KNO3 solutions from 0.0 to 1.0 m.
Supplement
Supplemental material for this article is available. It includes instructor notes, a discussion of instruments, an example spreadsheet for the instructor and a skeleton spreadsheet for the students, student materials and procedures, and other information needed to implement the experiment.
*  Contents JCE2001p1541W folder, with one Microsoft Word document and two Microsoft Excel spreadsheets.
*  Download
JCE2001p1541W.pdf

JCE2001p1541W.zip

JCE2001p1541W.sit
More Information
*  Citation
 Bonicamp, Judith M.; Loflin, Ashley; Clark, Roy W. J. Chem. Educ. 2001 78 1541.
*  Keywords
 Aqueous Solution Chemistry; Instrumental Methods; Laboratory Instruction; Physical Chemistry; Thermodynamics
*  History
 Created:
Last Updated:		 October 8, 2001
August 31, 2005
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 2001  > November  > Page 1541


Subscriptions
 Subscription Info
 Order Forms

JCE HS CLIC

Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
 JCE HS CLIC

Contributions Welcome
JCE welcomes your submission
 Contributors' Corner

Advertisers
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.
 Recent Advertisers

Be An Ambassador
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.
 Outreach with JCE

Comments to
jceonline@chem.wisc.edu		 Copyright © Division of Chemical Education, Inc., American Chemical Society.
All rights reserved.