Haifu Zheng, Yuming Ma, Yeqiang Cai

Chemical Institute of Metrology, Jiangsu Institute of Metrology (JSIM) Nanjing, 210023, China

Abstract: This paper discuss the reason why it is impossible to adopt strict thermodynamic treatment and accurately measure the quantity of solution pH . Taking three batteries as an example, the principle, hypothetical conditions and ionic strength of the method of measuring electromotive force are described in detail. At the same time, the quantitative data of the experiment about pH are given as evidence, and the rationalization error analysis is proposed.

Keywords: Determination of pH ; Single ion activity; Stand buffer solution; Debye-Huckel limit formula; Ionic strength