The pH Scale
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The pH scale ranges from 0 to 14.
It measures the acidity or basicity of a solution.
A pH of 7 means it is a neutral solution.
Pure water has a pH of 7.
A pH of less than 7 means the solution is acidic.
A pH of more than 7 means the solution is basic.
The less pH, the more acidic the solution is.
The more pH, the more basic the solution is.
pH stands for the power of H, or the amount of H+ ions acids or bases take or contribute in solution.
pH equals the negative log of the concentration of H+.
pH = -log[H+]
When the concentration of H+ ions in a solution is 10-14, the pH is 14.
In pure water, the average concentration of H+ ions is 10-7.