Abnormal Phenomena in Aspirin Functional Group Detection Experiments
QIN Lei1‡**, KANG Ze-Wei2‡, CAO Kui3
1. Tianjin Academy of Educational Sciences, Tianjin 300191, China; 2. Tianjin No. 50 Middle School, Tianjin 300100, China; 3. Middle School Affiliated to Renmin University of China, Beijing 100080, China
Abstract In the aspirin functional group detection experiment,two anomalous phenomena were observed: During carboxyl group analysis,the solution exhibited intensified red coloration 24 hours after adding litmus solution; in ester group analysis,when NaHCO3 solution was added to neutralize the catalyst dilute sulfuric acid,no purple coloration was observed after adding ferric chloride solution unless NaHCO3 concentration was controlled. To address these anomalies,a series of experimental investigations were conducted focusing on the acidity of aspirin hydrolysis products,hydrolysis reaction conditions,and regulation of Fe3+ chromogenic reactions with hydrolysis products. Building on this foundation,UV spectrophotometric analysis was performed to study “purple color gradation of salicylic acid coordination with Fe3+ at different concentrations”,which enabled estimation of salicylic acid yield and hydrolysis rate during aspirin degradation. Finally,solutions for abnormal phenomena were systematically analyzed from two dimensions—analytical sample sources and detection methodologies—while optimizing the aspirin functional group detection protocol. These findings provide reference for experimental design and operational protocols in multi-functional compound analysis.
QIN Lei, KANG Ze-Wei, CAO Kui. Abnormal Phenomena in Aspirin Functional Group Detection Experiments[J]. Chinese Journal of Chemical Education, 2026, 47(13): 89-95.
