Video summaries: pH and pKa relationship for buffers

So if pH is equal to pKa then the concentration of A- over the concentration of HA is equal to one and the concentration of A- is equal to the concentration of HA. And if pH is bigger than pKa then the concentration of A- over the concentration of HA is less than one and the concentration of A- is bigger than the concentration of HA. Lastly, if pH is less than pKa then the concentration of A- over the concentration of HA is bigger than one and the concentration of A- is less than the concentration of HA. Using this tool we can know almost immediately the relationship between our acid and it’s conjugate base in our solution.