Enter the pH value into the calculator to determine the hydroxide ion (OH-) concentration in moles per liter (mol/L).
OH- Concentration Formula
The following formula is used to calculate the hydroxide ion (OH-) concentration from the pH value:
[OH-] = 10<sup>-14 + pH</sup>
Variables:
- [OH-] is the hydroxide ion concentration (mol/L)
- pH is the measure of the hydrogen ion concentration
To calculate the OH- concentration, use the formula above where the pH value is subtracted from 14 and then used as a negative exponent with base 10.
What is OH- Concentration?
OH- concentration is a measure of the amount of hydroxide ions present in a solution. It is an important parameter in chemistry, particularly in the context of acid-base reactions and pH. The concentration of OH- ions in a solution determines its basicity and is inversely related to the concentration of hydrogen ions (H+), which determines acidity.
How to Calculate OH- Concentration from pH?
The following steps outline how to calculate the OH- Concentration from pH.
- First, determine the pH value of the solution.
- Next, use the formula [OH-] = 10-14 + pH to calculate the OH- concentration.
- Finally, enter the pH value into the calculator to get the OH- concentration in mol/L.
Example Problem :
Use the following variables as an example problem to test your knowledge.
pH value = 7.0
Using the formula, the OH- concentration is calculated as:
[OH-] = 10-14 + 7.0 = 10-7 mol/L