I assume 1 M/pH means 1 mol in a liter for a pH of 1.0
First, determine the ratio of base(b) to acid(a).
4.76 = 4.76 + log (b/a)
b/a = 1 or b=a initially. You should confirm that.
Than make an ICE table. We will work this backwards since we want to know how much to start with. We will call the amount we start with x. Since b = a then both will be x
....HAc + OH^- ==> Ac^- + H2O
I....x....0........x......
add.......1................
C...-1...-1........+1
E...x-1...0.......x+1
Now plug the E line into the HH equation and solve for x. The pH will be 5.76 (for the pH change of 1)
5.76 = 4.76 + log[(x+1)/(x-1)]
x = ? I calculated 1.22 mols/L but you should confirm that AND you should make an ICE table starting with 1.22 M with HAc and Ac^- and see if that gives you a 5.76. If it does that means that amount of HAc and Ac^- will provide enough material to allow 1 mol/L NaOH to be added and the pH will not rise above 5.76.
You wish to prepare a pH 4.76 acetic acid sodium acetate buffer with a buffer intensity of 1 M per pH. What concentrations of acetic acid and sodium acetate are needed?
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