Calculate the Ka for the acid.?
Enough of a monoprotic acid is dissolved in water to produce a 1.20 M solution. The pH of the resulting solution is 2.56.
- hcbiochemLv 71 month agoFavourite answer
Equilibrium: HA(aq) <--> H+(aq) + A-(aq)
Ka = [H+][A-] / [HA]
From the pH, [H+] = 10^-pH
[H+] = 2.75X10^-3 M
From the equilibrium, [H+] = [A-] = 2.75X10^-3 M
[HA] = 1.20 - 0.003 = 1.20
Ka = (2.75X10^-3)^2 / 1.20 = 6.3X10^-6