Jawabanmu

2014-02-21T19:32:10+07:00
2. pH = 4 ---> [H+] = 1 x 10^-4
[H+] = derajat ionisasi x M asam
10^-4 = 0,005 x M asam
M asam = 0,02 M

[H+] = √ Ka x M asam
10^-4 = √ Ka x 0,02
(10^-4)^2 = Ka x 0,02 ..
10^-8 = Ka x 0,02
Ka = 5 x 10^-7