Acids / Bases

The Acid/Base section allows you to calculate the pH given either the H3O+ concentration or the OH- concentration. Also, you can calculate the concentrations of OH- and H3O+ from the pH.

A pH value is an indication of whether a substance is acidic or basic. If the value is low (0-6), it is considered to be an acid. 7 is neutral. Values greater than 7 are referred to as basic. To determine the pH of a substance, you must have the concentration of hydronium ions (H3O+) or hydroxide ions (OH-). If you have the pH, you can determine the concentration of the hydronium ions and hydroxide ions.  The equations for pH is the -Log(Hydronium Ion Concentration).

Be sure to enter exponential values correctly. 1 x 10-3 is written 1E-3. 4.2 x 105 is written as 4.2E5.