pH indicators change color at their _____. The pH at which the color change happens for a particular indicator molecule depends on its:
A. pKa; concentration.
B. pKa; Ka or Kb.
C. equivalence point; Ka or Kb.
D. equivalence point; concentration.
Is the correct answer A?
actually it is b.
"Nah" Is correct, it is b
A solution of indicator molecules takes on the color of the most abundant form - wither the protonated or the unprotonated form. pH indicators change color at their pKa where the identity of the most abundant form changes. The pH at which the color change happens for a particular indicator depends on its Ka of Kb because this value determines the pH of the equivalence point.
The answer is b
Oh Robert, when will you ever learn
Yes, the correct answer is A.
pH indicators change color at their pKa. The pKa value of an indicator molecule represents the pH at which it is half-dissociated into its acidic and basic forms. At this point, the color change of the indicator is most pronounced. The concentration of the indicator molecule does not determine the pH at which the color change happens but can affect the intensity of the color change. Therefore, the correct answer is A: pKa; concentration.