2017 年 41 巻 2 号 p. 205-212
The decomposition of hydrogen peroxide by manganese dioxide as a catalyst is one of the most widely used reactions for teaching different concepts of chemistry, such as oxygen generation, catalytic reactions, and reaction stoichiometry. However, the problem of waste minimization of used catalysts is not paid enough attention in educational experiments. This research investigates the effect of a clay block containing manganese dioxide. By using this clay block, it turns out that oxygen is easily collected without downward displacement of water, and an up-and-down motion of the block like “Dancing Raisins” is observed simultaneously. This phenomenon is effective for inquiry-based science as a process, for (a) posing a productive question, (b) teacher-supported brainstorming activities, (c) a written job performance, (d) class presentation and reflection on students’ learning. In addition, clay blocks containing manganese dioxide are easily collected and reused, and thus are effective in green chemistry.