Understanding the Implicit Concepts in Measurement of Ion Transference Number and Ion Mobility by Using the Moving Boundary Method
ZHANG Chun-Fang1**, HUO Bing-Nan1, HAN Lin-Yu1, YAO Ning1, SHEN Fu-Gang1, SHANG Yan-Li1, SUN Su-Fang1, SHAN Jin-Huan1, MA Zhi-Guang1
College of Chemistry & Environmental Science, National Experimental Teaching Demonstration Center of Chemistry, Hebei University, Baoding 071002, Hebei
Abstract Based on one basic electrochemical experiment in physical chemistry, measurements of ion transference number and ion mobility by using moving boundary method, we discussed (1) the expressions for ion transference number of H+; (2) the ion transference numbers of Cd2+ and Cl－; (3) the uniform linear motions of the ions with constant current; (4) the solutions to obtain the potential gradients of H+ and Cd2+; (5) the linear relationship between molar conductivity and ion mobility; (6) the electrochemical reactions in the experiment, etc. In order to analyze all the above concepts and relations, we did three experiments at different conditions and examined all the ideas carefully, especially the first four items. In the end, all the ideas were well explained. Our work is helpful to integrate the fragmental concepts and the knowledge of multiple disciplines such as chemistry and physics, which is also helpful to optimize the knowledge system based upon real problems and to improve the core ability of the students in chemistry in the end.
ZHANG Chun-Fang, HUO Bing-Nan, HAN Lin-Yu, YAO Ning, SHEN Fu-Gang, SHANG Yan-Li, SUN Su-Fang, SHAN Jin-Huan, MA Zhi-Guang. Understanding the Implicit Concepts in Measurement of Ion Transference Number and Ion Mobility by Using the Moving Boundary Method[J]. Chinese Journal of Chemical Education, 2020, 41(14): 96-101.
