ERIC Number: EJ1036289
Record Type: Journal
Publication Date: 2014-Aug
Abstractor: As Provided
Reference Count: 17
A Simple Educational Method for the Measurement of Liquid Binary Diffusivities
Rice, Nicholas P.; de Beer, Martin P.; Williamson, Mark E.
Journal of Chemical Education, v91 n8 p1185-1190 Aug 2014
A simple low-cost experiment has been developed for the measurement of the binary diffusion coefficients of liquid substances. The experiment is suitable for demonstrating molecular diffusion to small or large undergraduate classes in chemistry or chemical engineering. Students use a cell phone camera in conjunction with open-source image processing software to measure concentrations of a colored species in a clear liquid, as a function of position and time. Three fundamental principles in mass transfer and spectrophotometry are demonstrated: Fick's first and second laws of diffusion and the Beer-Lambert law for absorption of light. The measured value for the binary diffusion coefficient for potassium permanganate in water using this method was found to be within 10% of literature values at the 95% confidence interval.
Descriptors: Science Instruction, Chemistry, Science Experiments, College Science, Undergraduate Study, Engineering, Photography, Telecommunications, Handheld Devices, Technology Uses in Education, Computer Software, Molecular Structure, Measurement Techniques, Scientific Principles, Spectroscopy
Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: firstname.lastname@example.org; Web site: http://pubs.acs.org/jchemeduc
Publication Type: Journal Articles; Reports - Descriptive
Education Level: Higher Education; Postsecondary Education
Authoring Institution: N/A