The discussion revolves around the choice of indicators for determining the equivalence point in a titration, specifically comparing phenolphthalein and bromothymol blue at a pH of 7. Participants explore the effectiveness of each indicator based on their pH transition ranges.
The discussion is ongoing, with participants presenting differing views on the suitability of each indicator. Some have offered reasoning for their preferences, while others are seeking clarification on the best choice based on the titration setup.
There is a lack of consensus on which indicator is more appropriate, with participants considering different scenarios regarding the placement of acid and base in the titration setup.
Actually, that is not quite right. The best indicator to use for a titration is one which the equivalence point (pH) falls into the range - preferably the middle - of the indicator. In this case, the bromothymol blue would be ideal, because it would change colour when the pH equals about 7. The phenolphthalein won't even start to change colours.zwtipp05 said:My guess would be that since 7 falls inside the range for the blue you would have to stop the titration while the color is still mixed. With phenolphthalein you stop when it completely changes color which makes it easier to obtain consistent results rather then trying to interpret the mix of colors.