At what point in the following titration curve would the pH of the solution be equal to the pKa of the acid?11.gif
(a) 0 mL
(b) 50 mL
(c) 95 mL
(d) 100 mL
(e) 120 mL
Chemistry · Sun Jul 10 2022
Answered on
The pH of a solution during a titration depends on the concentrations of the acid and base involved, as well as the volume of each solution being added. The pKa of an acid is the pH at which it is half dissociated. In this case, we need to find the point in the titration where the pH of the solution is equal to the pKa of the acid.
In a titration, a measured volume of a solution with a known concentration (called the titrant) is gradually added to a solution of the substance being analyzed (called the analyte) until the reaction between the two is complete. The pH of the solution being analyzed can change depending on the nature of the acid and base involved.
The titration curve is a graphical representation of the pH of the solution being analyzed as a function of the volume of titrant added. It typically shows a gradual change in pH followed by a steep change near the equivalence point (the point at which the reaction between the acid and base is complete).
To determine where the pH of the solution is equal to the pKa of the acid, we would look for the point on the titration curve where the acid is half dissociated. At this point, the concentrations of the acid and its conjugate base are equal, resulting in a pH equal to the pKa of the acid.
Looking at the given options: (a) 0 mL, (b) 50 mL, (c) 95 mL, (d) 100 mL, and (e) 120 mL, we would need to analyze the titration curve or have additional information about the specific acid and base involved to determine the exact point where the pH is equal to the pKa.