TCE ForumWhats NewSearchOrders


The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 16 (2011) pp 76-78

Comparing the Spectral Temperature of Incandescent and Compact Fluorescent Light Bulbs

Raymond C. Dudek*,†, Neil T. Anderson, and Jessica M. Donnelly

†Department of Chemistry, Wittenberg University, P.O. Box 720, Springfield, OH 45501, ‡Department of Molecular & Cellular Physiology, University of Cincinnati College of Medicine, P.O. Box 670576, Cincinnati, OH, 45267
Received August 6, 2010. Accepted September 23, 2010.

Published: 25 February 2011

Abstract. The visible spectrum of a compact fluorescent (CF) light bulb is recorded and then compared to the spectrum of a commercially equivalent, incandescent light bulb. Due to different methods of light generation, the spectra are qualitatively very different from each other, making direct comparisons difficult. The incandescent light bulb spectrum can be modeled as a blackbody radiation source using Plank’s radiation equation. Portions of the CF light bulb spectra are fitted to the same equation in order to generate an effective spectral temperature. Different fitting routines are developed and evaluated by the students. The spectral temperatures of the two light bulbs can be compared to each other and the manufactures’ specifications. Through this experiment, students will learn about visible spectroscopy, spreadsheet programming, and computer modeling of experimental data. As light bulb technology continues to advance, new bulbs can be evaluated, making this an open-ended lab. This experiment is a quick, safe, and fast introduction to spectroscopy and computer modeling.

Key Words: Laboratories and Demonstrations; physical chemistry; quantum mechanics

(*) Corresponding author. (E-mail:

Article in PDF format (60 KB) HTML format

© The Chemical Educator 1996-2017