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What is measured as pH is logarithm taken from hydrogen ion concentration in moles per liter, mathematically often expressed as following:
pH = - log10[H+H+]
It describes the acidity or alkalinity of a solution, for example used in an industrial process. Lower case letter p stands for negative base ten logarithm ad the upper case letter H stands for element hydrogen
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Reference electrode is made using chemical solution that is neutral pH buffer solution that is allowed to exchange ions with the process solution through a porous separator, forming low resistance connection to the test liquid. This electrode creates a reference that it both tries to maintain and that on which to compare potential readings from the measurement electrode. Reason for usage of wet chemical interface is that they produce less voltage across the interface of contact, allowing for more accurate measurements [1].
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