Recording absorption spectra with a Spectronic 20 can be a monotonous and time-consuming process since students must adjust the wavelength control knob and manually set the 0 and 100% transmittance with a blank prior to making a measurement at each wavelength. This article describes how simple modifications to the Spectronic 20D+ and interfacing this instrument to a popular data acquisition system allows for a ∼10-fold decrease in the time necessary for collection of an absorption spectrum from 400 to 650 nm.
Supplement
Instructions for modifying the Spectronic-20D+ spectrophotometer and infromation about setting up the Vernier LabPro and software are available.
The "Chemistry Teacher Connection" (CTC) is especially for high school chemistry teachers. For only $40/year, it offers an online-only subscription to CLIC along with membership in the Division of Chemical Education, normally $65/year. CTC subscribers receive access to all articles and supplements from 1996 through the current issue.
Through special arrangement with the ACS, JCE High School CLIC is now able to provide subscribers with online access to Chemical & Engineering News articles that have been selected specifically for secondary science instructors and their students.
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