Abstract By using acid-base titration, we determined the suitability of phenolphthalein and methyl red as acid base indicators. We found that the equivalence point of the titration of hydrochloric acid with sodium hydroxide was not within the ph range of phenolphthalein's color range. The titration of acetic acid with sodium hydroxide resulted in an equivalence point out of the range of methyl red. And the titration of ammonia with hydrochloric acid had an equivalence point …showed first 75 words of 1550 total…

…showed last 75 words of 1550 total…the equivalence point of found pH 8.6. And the titration of ammonia with hydrochloric acid had an equivalence point at a pH of 5.8. The methyl red indicator and the phenolphthalein indicator were unsuitable because their pH ranges for their color changes did not cover the equivalence points of the trials in which they were used. However, the methyl red indicator is more suitable, since it's pH range is closer to the equivalence points of the titrations.