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

JCE Print

JCE Digital Library

JCE Software

Only@JCE Online

About JCE


  Home > JCE Print > Journal of Chemical Education > Issues > 2008  > June  >
In the Laboratory
Visualizing the Solute Vaporization Interference in Flame Atomic Absorption Spectroscopy
Christopher R. Dockery
Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, GA 30144

Michael J. Blew and Scott R. Goode
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208

Cover
June 2008
Vol. 85 No. 6
p. 854

Abstract
Every day, tens of thousands of chemists use analytical atomic spectroscopy in their work, often without knowledge of possible interferences. We present a unique approach to study these interferences by using modern response surface methods to visualize an interference in which aluminum depresses the calcium atomic absorption signal. Calcium atomic absorption measurements are performed on solutions that contain calcium only, calcium plus aluminum, and calcium plus aluminum with lanthanum added as a releasing agent. The interferences are known to be affected by flame temperature, so measurements were made under conditions of varied flame stoichiometry and observation height. Results are displayed using response surfaces generated by regression analysis of the results of a factorial design in which burner height and fuel ratios are varied. Response surface methods allow students to recognize the tradeoffs required to optimize instrumental parameters. The user can chose to optimize operating conditions based on minimizing the solute vaporization interference, maximizing the absorbance, optimizing signal-to-noise ratio, or any combination of these three diagnostic parameters. The conditions needed for stable, reproducible chemical analyses were substantially different from those that produce the maximum signal.
Supplement
Student handouts including discussion questions
*
Download
Contents
More Information
*
Citation
Dockery, Christopher R.; Blew, Michael J.; Goode, Scott R. J. Chem. Educ. 2008, 85, 854.
*
Keywords
Analytical Chemistry; Atomic Spectroscopy; Calibration; Hands-On Learning / Manipulatives; Instrumental Methods; Laboratory Instruction; Problem Solving / Decision Making; Quantitative Analysis; Spectroscopy; Upper-Division Undergraduate
*
History
Created:
Last Updated:
5/5/2008
5/7/2008
  Home > JCE Print > Journal of Chemical Education > Issues > 2008  > June  > Page 854


Subscriptions

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.


Contributions Welcome
JCE welcomes your submission

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.

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.