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 > 2003  > September  >
In the Laboratory
The Solubility Product of PbCl2 from Electrochemical Measurements
Jimmy S. Hwang and Ghassan A. Oweimreen
Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
Cover
September 2003
Vol. 80 No. 9
p. 1051
Abstract
A new experiment suited for an undergraduate physical chemistry laboratory is presented. The students obtain the solubility product, Ksp, of PbCl2 at various temperatures from practically simultaneous emf measurements on two electrochemical cells. One half-cell is common to both cells. Each of the three half-cells is enclosed in a jacket of circulating water where the temperatures are controlled to better than ±0.05 K and measured to ±0.1 K. A 1 M KNO3 salt bridge is used in the two cells. At each temperature the difference between the two cells' emf values is directly related to the concentration of the Cl- ions in the saturated PbCl2 solution, which in turn yields the solubility product of PbCl2. The variation of ln Kspwith T-1 yields the standard enthalpy and entropy of the solubility equilibrium of PbCl2(s). Use of two cells to cancel out the temperature dependencies of the standard reference electrodes and junction potentials across the salt bridge is novel. This experiment is not found in physical chemistry laboratory textbooks. It works well and can be completed by the students within three hours.
Supplement
The background, relevant theory, and details of the experimental procedure are available.
*  Contents JCE2003p1051W.doc (Microsoft Word)
*  Download
JCE2003p1051W.pdf

JCE2003p1051W.zip

JCE2003p1051W.sit
More Information
*  Citation
 Hwang, Jimmy S.; Oweimreen, Ghassan A. J. Chem. Educ. 2003 80 1051.
*  Keywords
 Electrochemistry; Equilibrium; Laboratory Instruction; Lead; Physical Chemistry; Solutions / Solvents; Thermodynamics
*  History
 Created:
Last Updated:		 August 4, 2003
February 28, 2005
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 2003  > September  > Page 1051


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.