Phenolphthalein may be used as an indicator for the titration of:
A)a weak base with a strong acid
B)a weak acid with a weak base
C)any acid and base
D)a weak acid with a strong base
E)phenolphthalein cannot be used as an indicator

Question

Quizplus · Accepted Answer

Phenolphthalein is a suitable indicator for the titration of a weak acid with a strong base. This is because the pH at the equivalence point of this titration is around 8.2, which is within the range of the color change of phenolphthalein (pink to colorless). Phenolphthalein is not suitable for the titration of strong acids or bases with each other, as the change in pH at the equivalence point is too small to be detected by phenolphthalein. It is also not suitable for the titration of weak bases with strong acids, as the pH at the equivalence point is too low for phenolphthalein to show a color change.

Phenolphthalein May Be Used as an Indicator for the Titration