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Colorimetric analysis with camera phones & digital cameras

Professor R. Lee Penn's work on the introduction of colorimetric analysis with camera phones and digital cameras has been published in Journal of Chemical Education. Her co-author is alum Eric Kehoe, a teacher at Janesville Waldorf Pemberton High School in Janesville, MN. Their goal is to make the experiment school friendly with a simple, outlined protocol for conducting the experiment using a phone or digital reader. Kehoe has implemented this in his own classroom.

The abstract for the article is: A common task in chemistry is the determination of concentration of unknown compounds. The Beer–Lambert law, also commonly referred to as Beer’s law, enables the quantitation of the concentration of an absorbing analyte in solution. Results from experiments using solutions of blue food dye, lemon–lime sports drink, and iron(III) chloride demonstrated that absorbance versus concentration data are linear for data collected using digital cameras and camera phones. The key to obtaining reliable data is collecting a single image of samples, standards, and blanks arranged in front of a uniform light source, such as a light box or a computer screen. The approach provides a facile method for performing colorimetric analysis in a wide range of settings, from the high school chemistry laboratory, in the field, and the research laboratory.

Read the article. Michael Seery referenced the article is his blog, "Is this going to be on the exam?" Click here to read the blog.

Read the article, published in the September 25 edition of the Minnesota Daily.