The Ka of a monoprotic weak acid is 495Solution HAHA I017100

The Ka of a monoprotic weak acid is 4.95

.....HA...<=>...H+...+...A-

I...0.171.........0.........0

C....-a..........+a........+a

E..0.171-a.......a.........a

Ka = [H+][A-]/[HA]

= a^2/(0.171 - a) = 4.95 x 10^(-3)

a^2 + 4.95 x 10^(-3)a - 8.4645 x 10(-4) = 0

The positive root of the quadratic equation is:

a = 0.02672

[H+] = a = 0.02672 M

Percent ionization = [H+]/[HA]initial x 100%

= 0.02672/0.171 x 100%

= 15.6%