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The pH scale

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The pH scale

From the simple definition of pH being the negative log of the H+ ion concentration, [H+], pH = - log [H+] you already know the following:

Other Interesting Facts about the pH Scale

According to the Oxford Dictionary, the pH scale was originally introduced by the Danish biochemist S.P.L. Sorensen in 1909 using the symbol pH. Other symbols such as pH have been used in the past. The letter p is derived from the German word potenz meaning power or exponent of, in this case, 10.

You may argue that what have we learned by looking into historical origin of the term? Well, the origin of concept is interesting in that we sometimes need to develop concepts ourselves. A concept or tool becomes important if many people find it convenient and elegant.

The reality is that many chemists have used the pH scale and the p scales for many other quantities that they often take it for granted, without realizing the logic behind their usages. For example, we have used the pKa, pKb, pKw, notations by analogy to the pH notations with out asking a question.

Now that you know the pH is an exponent, the following relationship is obvious:

[H+] = 10-pH

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