Why Are Only 1-2 Drops of Indicator Used in a Titration Experiment?

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SUMMARY

The discussion centers on the use of 1-2 drops of Phenolphthalein indicator in titration experiments. It is established that this minimal amount is sufficient due to the indicator's high molar absorptivity, which allows for effective qualitative assessment of the endpoint. The concern raised by the student regarding the indicator reacting with acids and bases is addressed, confirming that the small volume does not significantly affect the titration results.

PREREQUISITES
  • Understanding of titration techniques
  • Knowledge of acid-base chemistry
  • Familiarity with indicators in chemical reactions
  • Basic principles of molar absorptivity
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  • Research the role of indicators in titration, focusing on Phenolphthalein
  • Learn about the concept of molar absorptivity and its implications in titrations
  • Explore different types of indicators and their appropriate usage in various titrations
  • Investigate common titration errors and how to avoid them
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Chemistry students, particularly those in high school, educators teaching titration methods, and anyone interested in mastering acid-base titration techniques.

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omg Chem Titration help fast!

Ok so I'm a gr11 student who just had a titration exeriment.. and there are a couple of things that are really screwing me over!

Okay so we used an indicator, Phenolphthalein, more specifically, and when we stopped the titration when it turned light pink.

My question is, why are only 1~2 drops in indicator used?

I thought that it would be because of the indicator itself would also react with the acids and bases...but I just need some clarification here.. Can someone help me out here?
 
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You only need that much to make the qualitative assessment; the indicator has a high molar absorptivity.
 

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