Titration - Calculating the endpoint

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Discussion Overview

The discussion revolves around calculating the expected endpoint of a titration involving 25 ml of 0.1M NaOH and 25 ml of 0.1M HCl. Participants explore how to determine the endpoint in terms of volume, pH, or moles, and clarify the requirements for the calculation.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Homework-related

Main Points Raised

  • One participant seeks clarification on how to calculate the endpoint of the titration, questioning whether it should be expressed as moles, molarity, volume, or pH.
  • Another participant notes the ambiguity in the question, suggesting it could refer to either the volume of titrant or the pH at the endpoint.
  • A participant proposes that if the question pertains to the volume of titrant, the volumes of the initial solutions would be equal due to their identical molarity.
  • There is a query about how to calculate the pH at the endpoint, with a participant expressing uncertainty about the formula needed for this calculation.
  • One participant asks whether the titration is a practical experiment or a theoretical exercise, noting that their experience has been primarily volume-based in titrations.
  • A reference to an acid/base titration curve calculation is provided, suggesting further reading for context.

Areas of Agreement / Disagreement

Participants express differing views on whether the endpoint calculation should focus on volume or pH, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

The discussion highlights uncertainties regarding the exact requirements for calculating the endpoint and the assumptions about the nature of the titration (practical vs. theoretical).

future_vet
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Hello,

I have titrated 25 ml of NaOH with 25 ml of HCl. Both are 0.1M.
I need to calculate the expected endpoint for the titration of the strong base with the strong acid.

I know that:
0.025 L x 0.1M = 2.5 x 10^-3 moles of NaOH and HCl each.
I know that I need the same volume of both to do the titration.

But what I don't understand is: how do I calculate the endpoint? What is it supposed to be, a mole amount, a M amount, a volume, a pH?...

Thank you,

J.
 
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Question is ambiguous for me. You are asked either about volume of titrant or about pH.
 
That's what I thought too...

So, if it is the volume of titrant, since the 2 chemicals have the same molarity, the volume of the initial solution would be equal to the volume of the titrant. So, if they ask for the volume, I can do it.

What if I have to calculate the pH at the endpoint? I know how to predict whether it will be above at or below 7.0 depending on what we start with and what the titrant is, but I am not sure what the formula is to find the exact pH...

Any idea?

Thank you!
 
Is this an actuall reaction you are doing or just on paper? In the past all titrations I've done have been volume based.
 

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