pH. Concept and scale

The pH is a fundamental measurement in chemistry and biology that indicates the degree of acidity or basicity of a solution. The concept of pH originated in the early 20th century when the Danish chemist Søren Sørensen proposed the term to describe the concentration of hydrogen ions in solution.

The pH scale ranges from 0 to 14, where 0 indicates the highest acidity and 14 indicates the highest basicity. The neutral point is at 7, which represents a concentration of hydrogen ions equal to that of hydroxyl ions in solution. A pH less than 7 indicates that the solution is acidic, while a pH greater than 7 indicates that the solution is basic. Each pH unit represents a 10-fold change in the concentration of hydrogen or hydroxyl ions.

pH is an important measurement in many scientific fields and industrial applications. In chemistry, pH is used to characterize the acidity or basicity of a solution, which can be critical for the synthesis of new compounds and the understanding of chemical reactions. In biology, pH is critical to the survival and function of cells, as many enzymes and proteins only function in a specific pH range. In medicine, pH is used in diagnostic tests, patient monitoring and drug development. In the food and pharmaceutical industry, pH is crucial to ensure the safety and stability of products. pH is also important in environmental management and water quality conservation.