|
View Ontology
| Name: | pH (Hydrogen Ion Concentration) |
| Acronym: | pH |
| Description: | The pH measures the effective acidity or alkalinity of a solution, It is expressed as the negative log of the hydrogen ion concentration. Pure water has a pH of 7 because it has a hydrogen ion concentration of 10-7 moles per litre under standard conditions. The pH ranges from 0 to 14 with 0 being extremely acidic and 14 being extremely alkaline,. Substances which are highly acidic tend to have hydrogen atoms that dissociate when there is sufficient water to produce free hydrogen ions. Dissociation rates change with temperature consequently pH values are temperature dependent. During the most problematic period the pH of precipitation in the rain was 4.1 in the northeastern US (in the 1096’s) but it generally increased as more pollution controls were put in place. In the case of domestic water, it is frequently treated to ensure the pH is not too low because acidic water can be very corrosive for the pipes. |
| Type: | Noun |
| Term is: | Attribute | | Term has: | Unit | | Term unit: | moles per litre | |
