ph defined in 1951 yearph - pH;
ph - A quantitative expression for acidity or alkalinity of a solution, i.e. concentration of hydrogen or hydroxyl ions. Scale ranges from o to 14, pH 7 being neutral, less than 7 acid, more than 7 alkaline. Concentration of hydrogen or hydroxyl ions increases or decreases ten times for each unit of change pH. Theoretically pH= -log(cH), where cH is the concentration of hydrogen ions in grams per litre.
near ph in Knolik
definition of word "ph" was readed 1009 times