The oil drop experiment: A rational reconstruction of the Millikan-Ehrenhaft controversy and its implications for chemistry textbooks

Research in science education has recognized the importance of history and philosophy of science. Given this perspective, it is important to analyze h ow general chemistry textbooks interpret Millikan's oil drop experiment. Th is study has the following objectives: (a) elaboration of a history and phi losophy of science framework based on a rational reconstruction of experime ntal observations that led to the Millikan-Ehrenhaft controversy; (b) formu lation of six criteria based on the framework, which could be useful in the evaluation of chemistry textbooks; and (c) evaluation of 31 chemistry text books based on the criteria. Results obtained showed that most textbooks la cked a history and philosophy of science framework and did not deal adequat ely with the following aspects. (a) The Millikan-Ehrenhaft controversy can open a new window for students, demonstrating how two well-trained scientis ts can interpret the same set of data in two different ways. (b) Millikan's perseverance with his guiding assumption shows how scientists can overcome difficulties with anomalous data. (c) Millikan's methodology illustrates w hat modern philosophers of science consider important issues of falsificati on, confirmation, and suspension of disbelief. (d) The experiment is diffic ult to perform even today, owing to the incidence of a series of variables. (e) Millikan's major contribution consists of discovering the experiment t o provide confirmation for the elementary electrical charge. (C) 2000 John Wiley & Suns, Inc.