pH stands for potential of hydrogen or power of hydrogen. It's a measure of how acidic or basic (alkaline) a solution is. The "p" represents the negative logarithm of the hydrogen ion (H⁺) concentration in a solution. A lower pH indicates a higher concentration of H⁺ ions and therefore a more acidic solution. Conversely, a higher pH indicates a lower concentration of H⁺ ions and a more basic solution.
Understanding the pH Scale
The pH scale typically ranges from 0 to 14:
- 0-6: Acidic (e.g., lemon juice, stomach acid)
- 7: Neutral (e.g., pure water)
- 8-14: Basic or Alkaline (e.g., baking soda, bleach)
Several sources confirm this definition: Wikipedia describes pH as "potential of hydrogen" and highlights its use in measuring acidity or basicity. Dictionary.com similarly defines it in a chemical context. ThoughtCo explains that pH stands for "power of hydrogen," with the "H" capitalized due to its elemental symbol. Numerous other sources (Sensorex, Study.com, Eska Blog, USGS) reinforce this meaning.
It's important to note that while "Ph" can also refer to a phenyl group in chemistry (Reddit r/chemhelp), in the context of measuring acidity, it invariably stands for potential of hydrogen. The capitalization of "pH" is also crucial for distinguishing it from other uses of "ph" or "Ph".
