The Oil Drop Experiment: Do Physical Chemistry Textbooks Refer to its Controversial Nature?

Abstract

Most general chemistry textbooks consider the oil drop experiment as a classic experiment, characterized by its simplicity and precise results. A review of the history and philosophy of science literature shows that the experiment is difficult to perform (even today!) and generated a considerable amount of controversy. Acceptance of the quantization of the elementary electrical charge was preceded by a bitter dispute between R.A. Millikan and F. Ehrenhaft, that lasted for many years (1910)(1911)(1912)(1913)(1914)(1915)(1916)(1917)(1918)(1919)(1920)(1921)(1922)(1923)(1924)(1925). The objective of this study was to investigate whether physical chemistry textbooks refer to the controversial nature of the experiment. Based on six criteria developed previously, 28 physical chemistry textbooks were evaluated. Analysis of the texts using six identified criteria demonstrated that the textbooks neither referred to the controversial nature of the experiment nor recognized the difficulty of the experimental procedure. Only a few texts even attempted to include any discussion of the history or philosophy of the experiment. The instructor of a physical chemistry course could include aspects of the Millikan-Ehrenhaft controversy to motivate classroom discussion and help facilitate an understanding of the role that controversy has in scientific progress.

Identifying and Addressing Student Difficulties with the Millikan Oil Drop Experiment

“…Although Segerstrale's article is not aimed at physics pedagogy, it does provide a solid background for a discussion of the research ethics of Millikan. Another perspective is provided by Niaz (2000), Niaz and Rodríguez (2005), and Rodríguez and Niaz (2004) who discuss the Millikan-Ehrenhaft controversy and its implications for textbooks and laboratory instructions.…”

“…Crease's insight, and similar insights of other historians and philosophers of science, is not generally promoted in science classrooms due to the inherent pressure to decontextualize and distil scientiWc knowledge before it is presented to students. As a result, contemporary textbooks often produce a caricature of experiments such as Millikan's in textbooks (Niaz and Rodríguez 2005;Rodríguez and Niaz 2004).…”

Science education for democratic citizenship through the use of the history of science

“…However, it is probably typical of the accounts of the story told in science textbooks (Niaz and Rodríguez 2005;Knain 2001). It emphasizes the role of the single scientist discovering the laws of nature in his laboratory through a well-designed experiment.…”

Consideración de la historia en los libros de texto de química

“…Traer la historia a colación implica tener que hablar de controversias y luchas entre científicos. Niaz y Rodríguez (2005) nos ejemplifican lo que significó la polémica entre Millikan y Ehrenhaft sobre la determinación de la supuesta carga elemental que representaba la del electrón y cómo la enorme mayoría de los libros de texto no la mencionan para nada. Nos dicen estos autores que su inclusión en las clases: "puede facilitar en los estudiantes el interés, motivación y comprensión de que las controversias juegan una parte importante en el progreso científico Es una buena práctica pedagógica permitir que los estudiantes echen una ojeada de cómo la indagación científica se conduce realmente en un laboratorio de investigación (en contraste con las presentaciones de los libros).…”