Design and Optimization of Teaching Experiment Based on Construction of Strong Oxidation of Concentrated Sulfuric Acid
LI Jia-Hao1, LI Ai2, LI Hong-Fei3, ZHANG Bin4, GAO Cong-Jun5, ZHANG Yan-Hua1, FU Jin-Song 1,6**
1. College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610068, China; 2. College of Chemistry and Chemical Engineering, Hainan University, Haikou 570228, China; 3. Chuxiong Yi Autonomous Prefecture, Yunnan Province Shuangbai County No.1 Middle School, Chuxiong 675100, China; 4. No.2 Middle School in Pidu District, Chengdu 611730, China; 5. Panzhihua Seventh Senior High School, Panzhihua 617005, China; 6. Sichuan Jiutian Wuyang New Materials Co., Ltd. Ziyang 641300, China
Abstract The reaction experiment between Cu and concentrated H2SO4 is an important experiment for senior high school students to understand strong oxidizing properties of concentrated H2SO4. According to the method given in the textbook, it was found that the reaction solution contained black insoluble substances, which interfered with students' understanding of the strong oxidizing nature of concentrated H2SO4. At the same time, the identification process of the product CuSO4 in the experiment was cumbersome and dangerous. To address this issue, experimental conditions were optimized from three factors: concentration of concentrated H2SO4, reaction temperature, and amount of Cu tablets used. The experimental results showed that the reaction could be clearly observed under the conditions of 5 mL H2SO4 concentration of 90%, reaction temperature of 180 ℃, and copper sheet mass of 0.1 g,the generation of white mist SO2, the presence of blue solution (CuSO4), and the absence of insoluble substances. The optimized experiment had a higher matching degree between the experimental phenomena and the chemical equation given in the textbook regarding the reaction, which could effectively help students construct the strong oxidation of concentrated H2SO4. At the same time, the operation process was simple, with less time, good safety, and enhanced reproducibility.
LI Jia-Hao, LI Ai, LI Hong-Fei, ZHANG Bin, GAO Cong-Jun, ZHANG Yan-Hua, FU Jin-Song. Design and Optimization of Teaching Experiment Based on Construction of Strong Oxidation of Concentrated Sulfuric Acid[J]. Chinese Journal of Chemical Education, 2025, 46(3): 66-70.
