University Chemistry ›› 2021, Vol. 36 ›› Issue (9): 2012053.doi: 10.3866/PKU.DXHX202012053

Special Issue: 分析化学课程与实验教学

• Chemistry Laboratory • Previous Articles     Next Articles

A Study on Influence Mechanism in Determination of Calcium Content in Dolomite by Potassium Permanganate Titration

Sijia Xiang1, Guangxu Liao1, Qizhi Yao1,2,*(), Gu Jin1, Lingling Li1,2   

  1. 1 School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China
    2 National Demonstration Center for Experimental Chemistry Education(University of Science and Technology of China), Hefei 230026, China
  • Received:2020-12-31 Accepted:2021-02-18 Published:2021-03-15
  • Contact: Qizhi Yao E-mail:qzyao@ustc.edu.cn

Abstract:

"Determination of calcium content in dolomite" is one of the important experiments in college analytical chemistry laboratory. During the experiment, students found that the initial redox reaction rates are significantly different between the calibration experiment of potassium permanganate solution by sodium oxalate standard solution and the titration experiment of calcium oxalate formed from dolomite by the calibrated potassium permanganate solution. Based on these experimental phenomena and combined with chemistry theory mastered by students, some conjectures and explanations were put forward. After that, we guided students to design experiments to explore and verify them. Through these experiments, it can not only answer the students' doubts, but also train and improve their ability to analyze and solve problems, and thus stimulating students' interest in chemical experiment learning.

Key words: Potassium permanganate method, Redox reaction, Calcium oxalate, Influence factors, Titration rate

MSC2000: 

  • G64