What Does pH Stand For

There are countless situations where the relative acidity or alkalinity of a substance or system is of critical importance. Agricultural conditions, water quality, food preservation, lung and kidney function—all are circumstances in which quantitative measures of acidity or basicity enable proper maintenance and regulation of vital processes. The term pH is widely used as an expression of acid/base content, but what is the origin of such nomenclature  

The value of the hydrogen ion concentration will accordingly be expressed by the hydrogen ion. and the factor will have the form of 

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