JCE Online Journal of Chemical EducationDivision of Chemical Education, American Chemical SocietyAmerican Chemical Society
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print
   Current Issue
 Previous Issues
 Supplements
 Search JCE Index

JCE Digital Library
   ChemInfo
 DigiDemos
 Featured Molecules
 LivTexts
 LrnCom
 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 > 2006  > May  >
Research: Science and Education
Factors That Influence Relative Acid Strength in Water: A Simple Model
Michael J. Moran
Department of Chemistry, West Chester University of Pennsylvania, West Chester, PA 19383
Cover
May 2006
Vol. 83 No. 5
p. 800
Abstract
The pKa's of diverse aqueous acids H–A correlate well with the sum of two gas-phase properties: the H–A bond-dissociation enthalpy (BDE) and the electron affinity (EA) of the A• radical. Acidity correlates poorly with each of these separately. It is suggested that rather than bond strength alone or bond polarity, the sum of the enthalpies of these two steps is a fairly good indicator of relative acidity, especially when comparison is made among acids of a given type. Electronegative groups attached elsewhere on the molecule have a greater effect on the acidity not in the weakening or polarization of the H–A bond, but rather in enhancing the electron affinity of the radical, or put another way, stabilizing the conjugate base.
More Information
*  Citation
 Moran, Michael J. J. Chem. Educ. 2006 83 800.
*  Keywords
 Acids / Bases; Aqueous Solution Chemistry; Atomic Properties / Structure; First-Year Undergraduate / General; Free Radicals; Inorganic Chemistry; Misconceptions / Discrepant Events; Textbooks / Reference Books
*  History
 Created:
Last Updated:		 3/16/2006
3/22/2006
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 2006 > May > Page 800


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.