A Colorful Activity to Introduce Kinetics and the Rate-Determining Step: Application to Metabolism and Metabolic Control Analysis

• Published in: Journal of chemical education Vol. 101; no. 1; pp. 181 - 186
• Main Authors: McCain, Daniel F., McCain, Evelyn K.
• Format: Journal Article
• Language: English
• Published: Easton American Chemical Society and Division of Chemical Education, Inc 09.01.2024; American Chemical Society
• Subjects: Chemical reactions; Chemistry; Control equipment; Kinetics; Metabolism; Organic Chemistry; Physical chemistry; Students; Teaching methods; First-Year Undergraduate/General; Hands-On Learning/Manipulatives; Enzymes; Upper-Division Undergraduate; Physical Chemistry; Biochemistry; Analogies/Transfer; Kinetics; Metabolism
• ISSN: 0021-9584; 1938-1328
• DOI: 10.1021/acs.jchemed.3c00624

The following activity was developed to allow students to actively participate in and measure the kinetics of a multistep process. Each group of students is given a stack of blank coloring pages, each with a rainbow design printed on it. Each student in a group is given a different color crayon and colors in their portion of the picture before passing it to the next student while being timed. The rates of each individual step of the process and the rate of the overall process are calculated. During this activity, students can observe the rate-determining step of a process, the accumulation of intermediates, and how the overall rate relates to the rates of the individual steps. It can be used during the teaching of kinetics and mechanisms within introductory chemistry, physical chemistry, or biochemistry. In the current report, it has been used as an analogy to metabolic pathways and to introduce metabolic control analysis (MCA) quantitatively. It involves no special equipment and minimal setup time on the part of the instructor.