The pH at the equivalence point is determined by the hydrolysis of the salt (you don't have an acid and a base at the equivalence point so you can't use the HH equation). You can calculate the concn of the salt at the eq point but let's call it z.
...........ClO^- + HOH ==> HClO + OH^-
I..........z.................0.....0
C..........-x................x.....x
E..........z-x...............x.....x
Kb for ClO^- = (Kw/Ka for HClO) =
(x)(x)/(z-x). Solve for x = (OH^-) and convert to pH.
Calculate the pH during the titration of 10.00 mL of 0.400 M hypochlorous acid with 0.500 M NaOH.
The Ka for HOCl is 3.0 x 10-8 M.
What is the pH at the equivalence point?
I used the HH formula and got pH=7.52+log(.222)=6.87, but its not right.
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