(259d) Teaching Students How to Develop Hypotheses for Experimentation in the Unit Operations Laboratory

The Unit Operations Laboratory is a critical course in the education of chemical engineering students. Very often, this course includes experiments that are prescribed, in which students follow standard operating procedures, make observations, and answer specific questions [1]. The results are reported using various methods, which can include written reports and oral presentations. The students’ understanding of the process is demonstrated in their presentation of results and ability to analyze data according to the theories they have presented and tested in the laboratory.

To encourage better understanding of the processes studied, students can approach the experiments with a set of more open-ended questions to answer. This will require students to design their own set of experimental tests to be conducted. This experimental work must follow from a logical set of hypotheses, based on the theories to be tested [2] [3] [4]. Formulating a good hypothesis will inform their experimental design and lead students through their experimental testing in a logical fashion.

In our experience, students have struggled to formulate reasonable hypotheses that are not superficial or “obvious” from basic observations and knowledge. To address this weakness, we have developed a set of activities and rubric criteria to give students guidance on how to formulate a good hypothesis for testing in the Unit Operations Laboratory.

In this paper, we will present one of those activities as well as the rubric language developed to support student formulation of strong hypotheses statements for experimental testing. Examples of typical student hypotheses (before and after the workshop) for various unit operations experiments will be shared and discussed. Survey results from students who participated in the activity will also be shared to show the perceived effectiveness of the activity.

References
[1] A. E. Ghadi and R. Mammucari, "An ac􀆟ve laboratory learning experience for chemical engineering students facilitated by hypothesis tes􀆟ng," in Research in Engineering Education Symposium & Australasian Association for Engineering Education Conference, Perth, 2021.
[2] B. R. Young, H. W. Yarranton, C. T. Bellehumeur and W. Y. Svrcek, "An Experimental Design Approach to Chemical Engineering Unit Opera􀆟ons Laboratories," Education for Chemical Engineers, vol. 1, no. 1, pp. 16-22, 2006.
[3] P. C. Price, R. Jhangiana, I.-C. A. Chiang, D. C. Leighton and C. Cutler, Research Methods in Psychology, Crea􀆟ve Commons Interna􀆟onal, 2017.
[4] S. Mcleod, "Research Hypothesis: Defini􀆟ons, Types & Examples," 6 March 2023. [Online]. Available:
htps://simplypsychology.org/what-is-a-hypotheses.html. [Accessed 30 March 2023].