The Van Deemter Equation

By Christa Colyer

Abstract

Developed for an upper-level undergraduate instrumental analysis course, this case actively engages students in an understanding of the abstract, often difficult to grasp, concepts of the van Deemter equation, important in the field of chemical separations. Students play the roles of stationary and mobile phases and solute molecules, and are asked to consider a series of questions that explore the reasons for their actions.

Download Case

Date Posted

03/13/2002

Overview

Objectives

Understand the factors that contribute to separation efficiency and/or peak broadening in chromatography.
Learn that eddy diffusion is caused by non-uniform packing of chromatographic columns.
Learn that longitudinal diffusion is caused by the tendency of a solute species to diffuse from regions of high concentration to regions of low concentration.
Learn that mass transfer in the form of partitioning of the solute into the stationary phase does not occur instantaneously and depends on the solute’s partition and diffusion coefficients.

Keywords

Van Deemter equation; eddy diffusion; stationary phase particles; solute molecules; longitudinal diffusion; mass transfer; chromatographic separation; chemical separation

Subject Headings

Analytical Chemistry

Chemistry (General)

EDUCATIONAL LEVEL

Undergraduate upper division

FORMAT

PDF

TOPICAL AREAS

N/A

LANGUAGE

English

TYPE/METHODS

Demonstration

Teaching Notes & Answer Key

Teaching Notes

Case teaching notes are protected and access to them is limited to paid subscribed instructors. To become a paid subscriber, purchase a subscription here.

Teaching notes are intended to help teachers select and adopt a case. They typically include a summary of the case, teaching objectives, information about the intended audience, details about how the case may be taught, and a list of references and resources.

Download Notes

Answer Key

Answer Keys are protected and access to them is limited to paid subscribed instructors. To become a paid subscriber, purchase a subscription here.

Note: There is no separate answer key for this case.