The concept of pH was first introduced by the Danish chemist Søren Peder Lauritz Sørensen at the Carlsberg Laboratory in 1909. The exact definition of “p” is unknown. Some references suggest it stands for “power;” others refer to the German word “potenz” (meaning power); still others refer to “potential.” In 2000, Jens Norby published a paper arguing that “p” is a constant and stands for “negative logarithm,” which has also been used in other works, and that “H” stands for hydrogen. Sørensen suggested the notation “pH” (power of hydrogen) as a matter of convenience as it abbreviates the logarithm for the concentration of hydrogen ions in solution. Although this definition has been superseded, pH can be measured with a calibrated electrode in a solution of known hydrogen ion concentration. Pure water is said to be pH-neutral. The pH of pure water at 25°C (77°F) is close to 7.0. Solutions with a pH of less than 7.0 are known as acidic and solutions with a pH greater than 7.0 are basic or alkaline. pH measurements are important in medicine, biology, chemistry, nutrition science, environmental science, oceanography and many other applications.
“Other” applications include, but are not limited to, the electronics manufacturing industry. Over the past 20 years, the common notion in this field has been that alkalinity is a MUST to remove flux residues. ZESTRON recently introduced the world’s first pH-neutral defluxing agents. These agents are designed to do a superior cleaning job, but also protect extremely sensitive materials and meet stricter rinse water disposal regulations.