Determine the ph of a 0.461 m c6h5co2h m solution if the ka of c6h5co2h is 6.5 x 10-5.

By using ICE table:

C6H5CO2H ↔ C6H5CO2 - + H +

intial 0.461 0 0

change - X + X + X

Equ (0.461 - X) X X

when Ka = [H+] [C6H5CO2-] / [C6H5CO2H]

6.5 x 10^-5 = X * X / (0.461-X) by solving for X

∴ X = 0.0054

∴[H+] = 0.0054

∴ PH = - ㏒[H+]

= - ㏒0.0054

= 2.27