Given that for ethanoic acid pKa=4.75, calculate the pH of sodium ethanoate 0.1M.

1 answer

C2H50Na + H2O ==> Na^+ + C2H5O^-
The ethanoate ion hydrolyzes as follows:
C2H5O^- + HOH --> C2H5OH + OH^-
Khydrolysis = Kb = Kw/Ka = (C2H5OH)(OH^-)/(C2H5O^-).

(C2H5OH) = y
(OH^-) = y
(C2H5O^-) = 0.1 - y
solve for y and convert to pOH and from there to pH.
Check my thinking. Post your wor if you get stuck.