Enter the concentration of conjugate base of acid, the concentration of hydrogen ions, and the concentration of chemical species (HA) into the Acid Dissociation Constant Calculator. The calculator will evaluate the Acid Dissociation Constant. 

Acid Dissociation Constant Formula

The following formula is used to calculate the Acid Dissociation Constant. 

Ka = A*H/HA

Variables:

  • Ka is the Acid Dissociation Constant ( )
  • A is the concentration of conjugate base of acid 
  • H is the concentration of hydrogen ions 
  • HA is the concentration of chemical species (HA) 

To calculate the acid dissociation constant, multiply the concentration of the conjugate base of acid by the concentration of hydrogen ions, then divide by the concentration of the chemical species.

How to Calculate Acid Dissociation Constant?

The following steps outline how to calculate the Acid Dissociation Constant.


  1. First, determine the concentration of conjugate base of acid.
  2. Next, determine the concentration of hydrogen ions. 
  3. Next, determine the concentration of chemical species (HA). 
  4. Next, gather the formula from above = Ka = A*H/HA.
  5. Finally, calculate the Acid Dissociation Constant.
  6. After inserting the variables and calculating the result, check your answer with the calculator above. 

Example Problem:

Use the following variables as an example problem to test your knowledge.

concentration of conjugate base of acid = 3

concentration of hydrogen ions = 4

concentration of chemical species (HA) = 10

Ka = A*H/HA =  ?