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Find the ph of a 0.250 m solution of nac2h3o2. (the ka value of hc2h3o2 is 1.80×10−5).

User Robasaurus
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1 Answer

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When NaC2H3O2 is in solution, it would act as a base since it ionizes into sodium ions and acetate ions, the acetate ions would interact with water with the following reaction:

C2H3O2- + H2O <---> C2H3O2H + OH-

So, from the reaction, hydroxide ions are formed giving it basic properties. We calculate as follows:

[NaC2H3O2] = [Na+] = [C2H3O2-] = 0.250 m

By the ICE table:
[C2H3O2-] C2H3O2H OH-
I 0.250 0 0
C -x +x +x
------------------------------------------------------------
E 0.250 - x x x

1.80×10^−5 = x^2 / (0.250 - x)

Solving for x, we have

x = 0.002112

pOH = -log 0.002112

pOH = 2.68

pH = 14 - 2.68 = 11.32


Therefore, the pH of the solution is about 11.32.

User Harman
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