Calculate pH of Buffer Step-by-Step Guide

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Discussion Overview

The discussion revolves around calculating the pH of a buffer solution after the addition of NaOH. Participants explore the methodology for determining pH in the context of a specific buffer system involving HONH2 and HONH3Cl, including the application of the Henderson-Hasselbalch equation.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant requests a step-by-step guide to calculate the pH of a buffer solution after adding NaOH.
  • Another participant suggests calculating the moles of each component and determining the amount of OH or H present to find the pH.
  • A different participant challenges this method, indicating it may not be correct.
  • One participant proposes using the Henderson-Hasselbalch equation, assuming a quantitative reaction with NaOH.
  • Another participant questions whether the calculated pH would be 6.18.
  • One participant recalls the Henderson-Hasselbalch equation and confirms its use with the moles of acid and base present.
  • Another participant notes that the pKa value used will affect the final pH calculation, suggesting that the ballpark estimate is reasonable.

Areas of Agreement / Disagreement

Participants express differing views on the correct method for calculating pH, with some supporting the use of the Henderson-Hasselbalch equation while others question the initial approach suggested. No consensus is reached on the exact steps or the final pH value.

Contextual Notes

There are unresolved assumptions regarding the reaction between NaOH and the buffer components, as well as the specific pKa value to be used in calculations.

disneychannel
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I have no idea how to find the pH of a buffer solution:
Please step by step!
Calculate the pH after 0.020 mol NaOH is added to 1.00 L of:
a mixture containing 0.100 M HONH2 and 0.100 M HONH3Cl

please step by step instruction so I can follow and do other problems on my own! Thanks
 
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its been a while but don't you just find the moles of each. then find out how many OH or H you have and find the ph like that? or was that not buffer?
 
i don't believe that's how you do it
 
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would the answer be 6.18?
 
ahhh the henderson hasslebach i remember that one. Yeah you just have to use that equation with the mols of acid and base taht you have.
 
Depends on what value you have used for pKa. Correct ball park for sure.
 
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