Question

What is the percent ionization of a 0.456 M aqueous solution of hydrosulfuric acid? K_a1 = 9.5x10^-8; K_a2 = 1x10^-19

Answer 1

H2S --------------> H+ +   HS-

0.456                      0          0

0.456 - x                 x           x

Ka1 = x^2 / 0.456 - x

9.5x10^-8 = x^2 / 0.456 - x

x = 2.08 x 10^-4

[H+] = 2.08 x 10^-4 M

% ionization = ([H+] / initial ) x 100

                     = (2.08 x 10^-4 / 0.456 ) x 100

% ionization = 0.0456