What is the Ka and pKa for a weak monoprotic acid with given titration data?

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Discussion Overview

The discussion revolves around calculating the acid dissociation constant (Ka) and its negative logarithm (pKa) for a weak monoprotic acid based on titration data, specifically focusing on the pH measurement after a certain volume of NaOH has been added. The context is primarily homework-related, involving theoretical and mathematical reasoning.

Discussion Character

  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • One participant presents a titration scenario involving 55.48 mL of NaOH used to titrate 25 mL of a weak monoprotic acid, with a pH of 4.96 after 31.64 mL of NaOH is added.
  • The same participant suggests using the equation pKa = pH + log(acid/conjugate base) to find pKa, but expresses uncertainty about the approach.
  • Another participant points out that the concentration of NaOH is not provided, indicating a potential gap in the information needed to solve the problem.
  • A later reply indicates that the initial poster has found a solution, though the details of that solution are not shared.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the necessary information to solve the problem, particularly regarding the concentration of NaOH. The discussion reflects uncertainty and varying levels of understanding about the approach to take.

Contextual Notes

The discussion highlights limitations such as the absence of NaOH concentration and the reliance on specific equations without clear definitions of terms like "acid" and "conjugate base." These factors may affect the ability to arrive at a solution.

feelau
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Homework Statement


Kk so the problem is that we have 55.48 ml of NaOH was required to titrate 25 mL of a weak monoprotic acid. After 31.64 mL of NaOH had been added, the pH is 4.96 for the solution. Calculate the Ka and pKa for this weak acid.

Homework Equations


pKa= pH + log(acid/conjugate base) maybe?
ka=products/reactants

The Attempt at a Solution


I wanted to make the NaOh and acid a ratio and then since we know what pH is, just use the first equation but I don't think that'll be correct. Other than that I'm not sure how to approach this. Help will be aprreciated thanks
 
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Not enough info. What is the concentration of NaOH?
 
the concentration isn't given, I copied the exact problem.
 
nevermind, i found out how to solve it
 

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