TEACHING CHEMOMETRICS WITH PHOTOGRAPHY EXPERIMENTS IN A UNIVERSITY COURSE ON EXPERIMENTAL DESIGN

Abstract

Stochastic methods have been proved to be very useful tools when we deal with multifactor chemical systems. On the other hand, chemometrics has been a necessary part of a curriculum in higher chemistry education and of a great and increasing interest as well. In this paper we propose an introduction to statistical methods dealing with multifactor chemical systems, by employing photography. The proposed experimental work concerns the determination of a photographic parameter, the contrast, also known as gamma γ, which is the slope of the characteristic curve of a photographic film. In practical sensitometry, the determination of γ has been based on the “single-factor-at-a-time” approach. Here we present a stochastic approach to development kinetics of a photographic emulsion. This application includes easy experiments and statistical treatment of the experimental data, and can be used as a tool for introducing chemometrics through photography and vice versa. In addition the obtained formulas can predict the slope γ of the characteristic curve of a photographic film and are useful to professional photographers or in the college photography lab. [Chem. Educ. Res. Pract. Eur.: 2000, 1, 393-399]