Origins: Why pH?
نویسنده
چکیده
cept for the first time, has probably wondered why chemists employ a scale for measuring hydrogen ion concentration which decreases in value as the concentration of the H+ ion increases and vice versa in other words, a scale in which a solution of pH = 1 is actually more acidic, rather than less acidic, than a solution having a pH = 14. The less mathematically inclined are also likely to be puzzled, if not irritated, by the sudden requirement that everything be done using logarithms rather than direct concentration values, as was previously done when working problems involving the solution concentrations of other ions. The answers to both of these questions are partly historical and partly scientific in nature and involve the work of the Danish biochemist, Søren Peter Lauritz Sørensen (1868-1939) (figures 1 and 4), who first pro-
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