Prev. Article Next Article Table of Contents

Demo

A Device To Emulate Diffusion and Thermal Conductivity Using Water Flow

Citing Articles

Your current credentials do not allow retrieval of the full text.

Purchase the full-text

PDF/HTML,
figures/images,
references and tables,
(where available)

Harvey F. Blanck

Department of Chemistry, Austin Peay State University, Clarksville, TN 37044

Thomas P. Gonnella

Department of Chemistry, Mayville State University, Mayville, ND 58257

J. Chem. Educ., 2005, 82 (10), p 1523

DOI: 10.1021/ed082p1523

Publication Date (Web): October 1, 2005

Section:

History, Education, and Documentation

Abstract

Time places severe limitations on which experiments can be demonstrated in the classroom. Since diffusion in liquids is a slow process, most classroom demonstrations of diffusion involve gaseous diffusion. They do not show quantitatively the relative concentrations of the diffusing substances nor do they demonstrate the various different general methods of determining diffusion coefficients. An acrylic plastic device has been designed using water flowing through a series of cells to visually emulate diffusion and thermal conductivity. Water height emulates concentration or temperature. It can emulate a steady-state condition in which there is a constant gradient of concentration or temperature change with distance as well as the approach to this steady state. It can emulate experiments in which mass diffuses across a boundary showing the resulting 1 - error function curve. It can emulate diffusion from a plane (point) source forming a Gaussian curve. Results are obtained in a matter of a few minutes. The lightweight, rugged plastic model is easy to transport, easy to use, easy to store, has no moving parts, and requires only water to operate. This mechanical device should be quite helpful in both classroom and laboratory discussions of diffusion and thermal conductivity.

Keywords (Audience):

Upper-Division Undergraduate

Keywords (Domain):

Demonstrations

Keywords (Feature):

JCE DigiDemos: Tested Demonstrations

Keywords (Pedagogy):

Analogies / Transfer

Keywords (Subject):

Solutions / Solvents

View: Hi-Res PDF | PDF w/ Links

Citing Articles

View all 2 citing articles

Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.

This article has been cited by 2 ACS Journal articles (2 most recent appear below).

Plastic Models Designed To Produce Large Height-to-Length Ratio Steady-State Planar and Axisymmetric (Radial) Viscous Liquid Laminar Flow Gravity Currents
Harvey F. Blanck
Journal of Chemical Education2012 89 (2), 234-238
- Plastic Models Designed To Produce Large Height-to-Length Ratio Steady-State Planar and Axisymmetric (Radial) Viscous Liquid Laminar Flow Gravity Currents
  Harvey F. Blanck
  Journal of Chemical Education2012 89 (2), 234-238
  Naturally occurring gravity currents include events such as air flowing through an open front door, a volcanic eruption’s pyroclastic flow down a mountainside, and the spread of the Bhopal disaster’s methyl isocyanate gas. Gravity currents typically have ...
  Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
Using Spreadsheets To Emulate Diffusion and Thermal Conductivity
Harvey F. Blanck
Journal of Chemical Education2009 86 (5), 651
- Using Spreadsheets To Emulate Diffusion and Thermal Conductivity
  Harvey F. Blanck
  Journal of Chemical Education2009 86 (5), 651
  Diffusion and thermal conductivity processes can be emulated using spreadsheets that use columns for increments in distance and rows for increments in time.
  Abstract | Hi-Res PDF | PDF w/ Links