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hianghao
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Homework Statement
I am trying to prepare a 1L Tris-HCl buffer 1M pH7. The pKa value is 8.06. The question is, how many molar of HCl should be added to produce this buffer?
Homework Equations
pH = pKa + log [base/acid]
The Attempt at a Solution
7=8.06 + lg (a/b)
-1.06=lg (a/b)
a/b = 0.0871 -----1
a+b= 1M
a=1-b --------2
Hence,
(1-b)/b = 0.0871
b = 0.92M
a = 0.08M
So, the molarity of HCl to be added is 0.92M or 0.08M. Why?