Abstract:

In the teaching process of "elemental chemistry experiments", freshmen may have some "abnormal" experimental results that deviate from the expected results or theoretical analysis due to the lack of consideration of the effects of temperature, catalyst, acidity, concentration or reagent dosage. Herein, some "abnormal" phenomena encountered by students in Mn elemental chemistry experiments are analyzed and summarized. The vivid and intuitive experimental demonstrations guide students to explore the possible causes of "abnormal" phenomena, to intuitively understand the effect of reaction conditions on the outcome of the reaction and to cultivate the students' ability of observation, analysis, judgment, induction, reasoning, and practical problem-solving.

Key words: Mn elemental chemistry experiments, Affecting factors, Abnormal phenomenon, Analysis and exploration