The origins of pH
In 1893, Soren Sorensen, a Danish chemist, was asked by the Carlsberg Laboratory to identify the best method for making quality beer.
Pour ce faire, Soren Sorensen se posa la question : « comment la fabrication des enzymes à partir des protéines s’effectuait-elle?» .Il s’est rapidement rendu compte que la concentration d’ions d’hydrogène avait un impact important sur la création des enzymes permettant la fabrication de bière de qualité. Après cette réalisation, il introduira le concept de pH et une échelle de concentration du pH afin de déterminer si une solution est acide ou basique.
What Is pH?
To begin, pH is an abbreviation for "hydrogen potential." Based on a scale of 0 to 14 and being logarithmic in magnitude, this simple identification technique makes it easy to understand a very complex chemical phenomenon.
In this situation, the logarithmic property of pH is explained as follows: a solution with pH=6 will be 10 times more acidic than a solution with pH=7 and a solution with pH=5 will be 100 times more acidic than a solution with pH=7 and so on.
What does pH measure?
The measurement of the pH is used to identify the number of hydrogen ions present in an aqueous or other solution, such as soil. In general, the concentration of hydrogen ions will be between 1 and 10-14 grams per litre.
Pure water, which is considered neutral, has a hydrogen concentration of 10-7 grams per litre, which corresponds to a pH=7.
In other words, an acidic solution contains more hydronium ions while a basic solution has more hydroxide ions.
How to measure the pH
Generally speaking, there are two techniques for identifying the pH of an aqueous solution. To begin with, the most common and simplest technique is the use of litmus paper or pH paper, which changes colour according to the pH of the solution. Although this technique is not the most accurate, it is effective, fast and simple. For more accurate results, the use of a pH electrode connected to a pH meter can provide more precise results on the concentration of hydrogen ions.