How to Calculate [HT-] in a Saturated Solution Using Titration Data?

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Discussion Overview

The discussion revolves around calculating the concentration of [HT-] in a saturated solution using titration data, specifically in the context of a homework problem involving KHT and NaNO3. Participants explore the implications of titration results, hydrolysis, and dissociation processes in determining solubility and Ksp.

Discussion Character

  • Homework-related
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant presents a titration result of 14.30 ml of 0.04M sodium hydroxide, using 2.005g KHT and 8.5g NaNO3, and suggests using an ICE chart to find [HT-].
  • Another participant questions whether the problem is simply asking for the titration result, implying a potential oversimplification of the task.
  • A different participant expresses skepticism about the simplicity of the question, noting that others in the class used an ICE chart.
  • One participant highlights the ambiguity of the question, stating that the titration is meant to determine the solubility of tartrate and that both hydrolysis and dissociation must be accounted for, suggesting that a simple ICE table may not suffice.
  • Another participant proposes a method involving known values for Ka1 and Ka2 and the pH of the saturated KHT solution to find the concentration of HA-, but notes that this approach does not utilize experimental results.
  • A participant mentions that the next part of the question involves finding the Ksp of KHT in the saturated solution, suggesting that dilution could be used to find [HT-] before applying it to an ICE chart for Ksp calculation.
  • One participant questions the dilution aspect, pointing out that only titration has been mentioned so far, and expresses uncertainty about using the ICE table for Ksp calculation, emphasizing the need to consider hydrolysis and dissociation.
  • A participant reflects on the complexity of the problem, noting that simple labs often overlook critical chemical processes, leading to uncertainty about what is expected in terms of accounting for these factors.
  • One participant concludes by stating they figured out the problem, indicating a resolution for themselves but not necessarily for the group.

Areas of Agreement / Disagreement

Participants express differing views on the simplicity of the problem and the necessity of accounting for hydrolysis and dissociation. There is no consensus on the best approach to solve the problem, and the discussion remains unresolved regarding the application of the ICE chart and the implications of the titration results.

Contextual Notes

Participants highlight potential limitations in the problem's wording and the assumptions about hydrolysis and dissociation that may not be explicitly stated. The discussion reflects uncertainty about the expected methodology and the relationship between experimental results and theoretical calculations.

jpd5184
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Homework Statement



show the calculation for [HT-] in your saturated solution for part 2.

titration- 14.30ml 0.04M sodium hydroxide
i used. 2.005g KHT and 8.5g NaNO3

i diluted the NaNO3 to 100ml and added 2g KHT. filtered it then titrated with sodium hydroxide.

Homework Equations



Ksp=[K+][HT-]
KHT---- K+ + HT-

The Attempt at a Solution



i figure i have to do a I.C.E chart to find this out and since KHT is a solid it has no effect.
and i do know that [K+]=[HT-]
 
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it could be but i don't believe it would be that simple, i saw other people in the class and they used an ice chart i think.
 
Question is ambiguous then.

Titration was to determine solubility of tartrate. Once you get total concentration you need to account for two processes - hydrolysis and dissociation. Simple ICE table won't work here, and in general this is not an easy problem.

However, I think it is possible to solve the question using a trick. Please see caculation of pH of amphiprotic salt. Equation 12.6 holds always. If you will find values for Ka1 and Ka2, and if you will find information about pH of saturated KHT solution, you will be able to find exact concentration of HA-. It happens that all three numbers are well known, especially pH of the saturated solution was thoroughly researched.

Problem is, with this approach you don't use results of your experiment.
 
they next part of the question which i didnt post says to find the Ksp(solubility product) of KHT in you saturated solution.

so maybe i just use dilution to find [HT-] and then plug this into a ICE chart to find the Ksp.
 
You have diluted something? So far you only said about titrated, saturated solution.

And I am not sure I know how do you want to use ICE table for finding Ksp. Assuming there were no hydrolysis and dissociation, you have just [HT-]=[K+].

Advanced rant:

I have checked - unfortunately, you can't ignore hydrolysis and dissociation, final concentration of HT- is substantially lower than the one determined by titration.

This is often problem with simple labs, they ignore part of the chemistry involved and you never know if you are expected to take everything into account, or not.

--
,
 
i figured it out, thank you.
 

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