pH

/ˈpiˌeɪtʃ/

/piˈeɪtʃ/

In chemistry, pH is a measure of how acidic something is. The lower the number on the pH scale, the more acid a substance contains.

The pH scale goes from 0 to 14, with 0 being the most acidic. The higher, low-acid numbers on the pH scale are basic — they feel slippery and have an astringent taste. Substances at around 7, the middle of the pH scale, are neutral, like water. Lemon juice has a pH of 2.2, since it's acidic. pH comes from the German word Potenz, "potency or power," and H, the chemical symbol for hydrogen.

Definitions of pH

1. noun

   (from potential of Hydrogen) the logarithm of the reciprocal of hydrogen-ion concentration in gram atoms per liter; provides a measure on a scale from 0 to 14 of the acidity or alkalinity of a solution (where 7 is neutral and greater than 7 is more basic and less than 7 is more acidic);
   synonyms: pH scale

   types:

   acidity

   pH values below 7

   alkalinity

   pH values above 7

   neutrality

   pH value of 7

   hyperacidity

   excessive acidity

   type of:

   hydrogen ion concentration

   the number of moles of hydrogen ions per cubic decimeter