What is the concentration of H3O+ ions in a solution of an acid HY that ionizes to produce H3O+ and Yions? Ka is 4.32 x 10-5 , and the final concentration of HY is 7.40 x10-2 mol/L.

Answer 1

K_a = [H₃O⁺][Y^-]/[HY]

4.32x10^-5=[H₃O⁺][Y^-]/7.40x10^-2

HY -> H₃O⁺ + Y^-

[H₃O⁺]=[Y^-]=x

4.32x10^-5=x²/7.40x10^-2

x=sqrt(7.40x10^-2 x 4.32x10^-5)=1.79x10^-3 mol/L