Based on the Henderson-Hasselbalch equation and the graph, we´re asked to **provide an estimate of the pK _{a} of the acid using data points A, B, and C**, and an

The graph corresponds to a Titration curve, where a strong acid is neutralizing a strong base.

This is indicated by the **equivalence point D**, where the pH is around 7 (indicated by a red horizontal line).

Remember that in the equivalence point, the volume of Acid and the volume of Base in solution are the same.

We determine pK_{a} at each point with the following steps:

*Step 1*: Determine the approximate values of pH at the graph.

Using the equation pH = pK_{a} + log{ [A^{-}] / [HA] } and the graph, provide an estimate of the pK_{a} of the acid using data from points A, B, and C. Report all 3 of the answers you calculate using this method as well as an average of the 3.