How does pH relate to H+ concentration?
- log [H+] = pH
The molar concentration of dissolved hydrogen ions in solution is a measure of acidity. The greater the concentration, the greater the acidity.
This concentration can range over a tremendous range, from 10^-1 to 10^-14. So a convenient way to scale down this range is the pH scale which means power of hydrogen.
Here is an example. If you have a hydrogen concentration of 0.1 molar, the pH is 1.0
-log[0.1] = 1.0
If you hydrogen concentration is diluted by a factor of 10 to 0.01 molar, then the pH is 2.0