Question

0.0400 M solution of HClO2, pH = 1.80 solve for Ka

Answer 1

Ka for weak acids is ---> Ka= (X)²/ (initial- X)

initial= 0.0400 M

to find X, you can find the H concentration using pH

[H+]= 10^-pH
[H+]= 10^-1.80= 0.016 which is X

ka = (0.016)²/ (0.0400 - 0.016) = 0.011