How much OH- must be added to achieve desired pH?

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To determine how much 5 M KOH is needed to raise the pH of 1.0 L of 0.1 M glycine from pH 9 to pH 10, the Henderson-Hasselbalch equation is utilized to calculate the concentrations of the protonated form (-NH3+) at both pH levels. The addition of KOH neutralizes the protonated glycine, shifting the equilibrium towards the free base (-NH2). By calculating the difference in the amounts of -NH3+ at pH 9 and pH 10, the required stoichiometry can be established to find the volume of KOH needed. The discussion emphasizes the importance of understanding the equilibrium and stoichiometric relationships in this acid-base reaction. Accurate calculations will lead to the correct amount of KOH necessary for the desired pH adjustment.
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Homework Statement


Glycine which has a pKa of 9.6 can exist in protonated form (-NH3+) or as the free base (-NH2) because of the reversible equalibrium R-NH3+ <------> R-NH2 + H+.

How much 5 M KOH must be added to 1.0 L of 0.1 M glycine at pH 9 to bring the pH to exactly 10?


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The Attempt at a Solution


I have spent a couple hours trying to figure this out but don't really know where to start. A couple hints might point me in the right direction
 
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When you add KOH to pH 9 glycine solution you are in fact neutralizing -NH3+.

Use Henderon-Hasselbalch equation to calculate amount of -NH3+ in solution at pH 9 and 10, then it is a simple stoichiometry.
 
Thanks Borek, very helpful :).
 

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