Answer:
buffer solution example:
sodium acetate + acetic acid
assume typical concentration of 0.5 M for Acetic acid, and 0.5 M for sodium acetate
then,
the pH equation
pH = pKa + log(acetate/Acetic acid)
since acetate = Acetic acid, then acetate/Acetic acid = 1
log(1) = 0
pH = pKa (acetic acid)
pH = 4.75
the pH will be on point, i.e. the 50-50% ratio
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