Electrometric determination of the pH of atmospheric precipitation

• DOI: 10.1007/bf00491827
• Publication Date: 2004-12-10T06:35:42Z
• Authors: V. D. Nguyen; P. Valenta
• Keywords: Acid rain; Sample (material)

Reliable pH-determination of rain water represents a difficult task both from the theoretical and practical point of view because the chemical composition and conductivity of rain water samples varies widely. The method for determining the pH is described that was used during our systematic study of the acidity of rain in various regions of the FRG from 1980 to 1985 and the problems encountered are discussed. Potential sources of error are inadequate sampling, sample storage, and electrometrical pH-determination of samples with a very low conductivity. The use of various types of electrodes, their pretreatment, storage and time response as well as the accuracy of the determination are discussed. Examples are given of the application of the method for determining the time dependence of the pH during single rain events in Julich as well as average monthly pH-values in polluted and nonpolluted regions in the Federal Republic of Germany.