pH is a measure of the acidity or basicity of a solution, while pKa is a measure of the strength of an acid. pH is determined by the concentration of hydrogen ions in a solution, while pKa is determined by the equilibrium constant of an acid dissociation reaction.
The Henderson-Hasselbalch equation can be used to calculate the pH of an aqueous solution with a known pKa and concentration of acid. The equation is pH = pKa + log([A-]/[HA]), where [A-] is the concentration of the conjugate base and [HA] is the concentration of the acid.
Yes, the pH of a solution can change if the concentration of acid remains constant. This can happen if there is a change in the concentration of the conjugate base, or if there is a change in the overall volume of the solution.
The addition of a strong base to an HA aqueous solution will result in an increase in pH. This is because the strong base will react with the acid to form its conjugate base, decreasing the concentration of hydrogen ions in the solution.
The lower the pKa value, the stronger the acid. This is because a lower pKa value indicates a higher equilibrium constant for the acid dissociation reaction, meaning the acid is more likely to donate a hydrogen ion in solution.