How to Prepare a Buffer Solution with a pH of 12.50 Using Given Reagents?

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To prepare a buffer solution with a pH of 12.50 using the available reagents, one can utilize sodium dihydrogen phosphate (NaH2PO4) as the buffering agent, along with strong bases like NaOH to adjust the pH. The Henderson-Hasselbalch equation can be applied, but it requires knowledge of equilibrium constants, which are not provided. While NaH2PO4 typically forms an acidic buffer, it can be adjusted with NaOH to achieve the desired pH. It's crucial to understand that strong acids and bases do not create buffer solutions, but they can help reach the target pH. Overall, careful calculations and adjustments are necessary to prepare the buffer solution effectively.
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Got a tough problem I have no clue how to do.

I have to prepare 500mL of a buffer solution with a pH of 12.50 and must be at least .10 M.

The only reagents I have are:
solid sodium dihydrogen phosphate dihydrate NaH2PO4 x (H2O)2
Distilled water
1.00 M NaOH(aq)
1.00 M HCL(aq)

Not all reagents need to be used. If I could get some help on how to do this problem, anything would be aprreciated.
 
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did you try the henderson-hasselbach equation?
 
Hederson-Hasselbach wouldn't work because you don't have any of the equillibrium constants such as Ka and Kb
I think its impossible because strong acids and strong bases don't create buffer solutions
 
Equilibrium constants can be looked up in chemistry books, and the NaH2PO4 is the buffering agent. The strong acid and strong base are for equilibrating it to the right buffering pH.
 
I see it now, my apologies, Henderson-Hasselbach would be in order. I believe the NaH2PO4 would ionize in water to form Phosphoric Acid and Sodium Phosphate. Then of course using the equation aformentioned to determine the pH. Then I'm afraid that i am baffled, because that would be an acidic buffer solution, and following a rule that was taught to me, an acid with 2 more oxygens then hydrogens is a strong acid, but there are exceptions and this may be one of them.
 
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