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 > 2004  > July  >
Research: Science and Education
A Simplified Calculation of the Real Confidence Interval in Analytical Methods
Javier Galbán
GEAS, Analytical Chemistry Department, Faculty of Sciences, University of Zaragoza, 50009 Zaragoza, Spain
Cover
July 2004
Vol. 81 No. 7
p. 1053
Abstract
This paper describes a detailed study of the imprecision of an analytical method resulting from the quantification step. Students use a mathematical model we developed to discover the effect of the different parameters on this imprecision. After applying this method with students we reached three main conclusions. First, the imprecision does not depend on the slope of the calibration line. Second, the imprecision does depend on the number (n) and the concentration of the calibration standards used, the analyte concentration in the sample to be analyzed, and the correlation coefficient (r) of the calibration line. Third, when the concentration of the calibration standards are equally spaced and the analyte concentration in the sample is close to the centroid of the line, the imprecision depends only on the n and r values. This model allows students to calculate imprecision more easily so that they will be able to apply this mathematical model both in their studies and their future professional activities.
More Information
*  Citation
 Galbán, Javier. J. Chem. Educ. 2004 81 1053.
*  Keywords
 Analytical Chemistry; CER Statistics; Chemical Education Research; Instrumental Methods; Quantitative Analysis; Statistics / Data Analysis; Teaching / Learning Aids
*  History
 Created:
Last Updated:		 May 27, 2004
January 19, 2005
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 2004 > July > Page 1053


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.