Solving pH Changes in Buffer Initial pH 4.45

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The discussion centers on calculating the pH changes in a buffer solution with an initial pH of 4.45 upon the addition of 1.00 mL of NaOH to 35 mL of water. A participant expresses confusion about the calculations, attempting to convert pH to [H+] and account for the moles of NaOH but arriving at incorrect results. It is noted that the measured pH after adding 1.00 mL of NaOH is 11.14, while with no NaOH added, the pH is 4.73. Participants highlight the lack of information regarding buffer concentration and type, which is essential for solving the problem accurately. The consensus is that without this information, the question remains incomplete and unsolvable.
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Homework Statement


If the initial buffer pH is 4.45, what is the pH when 1.00 mL NaOH is added to 35 mL of water?
Also, if 0.0 mL NaOH is added, what is the pH then?

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The Attempt at a Solution


I have no idea how to do this...all i can think of is to change the pH to [H+] and add the moles of that with the moles formed by NaOH (i tried using OH and using its pOH and finding the pH and converting back to H+) but when i add them together and divide by the total volume it's wrong...supposedly the measured pH for the addition of 1.00 ml is 11.14 and for the 0.00 added it's 4.73..thanks
 
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lha08 said:

Homework Statement


If the initial buffer pH is 4.45, what is the pH when 1.00 mL NaOH is added to 35 mL of water?

You are not given buffer concentration, nor buffer type? Then there is no answer to this question.

Also, if 0.0 mL NaOH is added, what is the pH then?

This one is easier. Once you add 0.0 mL of a strong base, pH doesn't change. But I suppose that's just a typo :smil:
 
Problem description is incomplete. Are you trying to solve a general problem?
 
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