Final answer:
In general, for titrations of strong acids with strong bases, any indicator with a pKin between about 4.0 and 10.0 will do. For the titration of a weak acid, use an indicator such as phenolphthalein or thymol blue with a pKin > 7.0. For the titration of a weak base, use an indicator such as methyl red or bromocresol blue with a pKin < 7.0.
Step-by-step explanation:
In general, for titrations of strong acids with strong bases (and vice versa), any indicator with a pKin between about 4.0 and 10.0 will do. For the titration of a weak acid, however, the pH at the equivalence point is greater than 7.0, so an indicator such as phenolphthalein or thymol blue, with pKin > 7.0, should be used. Conversely, for the titration of a weak base, where the pH at the equivalence point is less than 7.0, an indicator such as methyl red or bromocresol blue, with pKin < 7.0, should be used.