January 16, 2025, 03:12:54 PM
Forum Rules: Read This Before Posting


Topic: Titration Process Questions  (Read 4134 times)

0 Members and 1 Guest are viewing this topic.

Offline Atome

  • Regular Member
  • ***
  • Posts: 78
  • Mole Snacks: +2/-3
Titration Process Questions
« on: April 07, 2008, 05:27:24 PM »
Hello there,

I am not sure if my educated guesses for the following two questions are correct, and would appreciate help or confirmation.

Thanks!

---

1. Distinguish between equivalence point and the endpoint in a titration. Why might they be different? How would this affect the result of a titration?


My guess is that to perceive the equivalence point, the endpoint would need to exceed slightly the equivalence point to see the indicator change colour. This would cause the titration to have a higher concentration of base.

2. It is proper to put the two solutions for a titration in clean, dry beakers. You do not need to dry the Erlenmeyer flask to which you add the solutions, however, if it has been thoroughly rinsed with distilled water. Explain this procedural difference.

I am thinking that since the indicator for the titration is added to the flask, then as long as there are hydronium and hydroxide ions in the flask, titration can take place as normal.

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27895
  • Mole Snacks: +1816/-412
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: Titration Process Questions
« Reply #1 on: April 07, 2008, 05:52:21 PM »
1st - you are not answering the question. Distinguish.

2nd - what it really asks is why distilled water doesn't interfere.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Atome

  • Regular Member
  • ***
  • Posts: 78
  • Mole Snacks: +2/-3
Re: Titration Process Questions
« Reply #2 on: April 07, 2008, 06:16:50 PM »
Thanks for your reply.

1. Well, the equivalence point is when the number of moles in the acid is equal to the number of moles in the base.

The endpoint is when the indicator changes colour to indicate a neutralisation reaction.

2. I am guessing that distilled water would not interfere in the flask, but would interfere in the buret since it would dilute the base.

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27895
  • Mole Snacks: +1816/-412
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: Titration Process Questions
« Reply #3 on: April 07, 2008, 06:26:17 PM »
2xOK, although these answers are not sufficient.

1 - think about some example, like NaOH/HCl in the presence of phenolphthalein. What is end point pH, what is equivalence point pH? What happens to the determination result?

2 - just elaborate why.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Sponsored Links