PH
This is an old revision of this page, as edited by Dpbsmith (talk | contribs) at 15:55, March 4, 2007. It may differ significantly from current revision.
For technical reasons this article is titled "PH" The title should be "pH." pH measures the acidity or basicity of a (chemical) solution.
Solutions having a pH that is less than 7 are called "acidic". Solutions having a pH greater than 7 are called "basic".
pH equal to 7 is considered to be neutral. This is the pH of pure water at a temperature of 25 °C.
pH is a logarithmic scale. Roughly, it can be considered to be based on the concentration of protons(H+) in the solution.[1] Thus, a change of pH by 1 corresponds to a change in concentration by a factor of 10. In general, the pH of most substances varies from 0 to 14 although for some extreme cases the pH can be greater than 14 or less than 0.
Notes and references
- ↑ Actually, it is based on something called the hydrogen ion activity. Activity is approximately the same as concentration for dilute solutions in nearly pure water.