An aqueous solution contains 0.223 M carbonic acid and 0.112 M hydrobromic acid.
Calculate the carbonate ion concentration in this solution.
[CO32-] = mol/L.
Can you please help me how to solve this problem?
There are two ways to do this, a long way and a short way.
The short way is to combine the k1 and k2 for carbonic acid this way.
H2CO3 --> 2H^+ + CO3^2-
k1k2 = (H^+)^2(CO3^2-)/(H2CO3)
You have H2CO3, and H^+ (from the HBr), substitute and solve for CO3^2-
(Note: The ionization equation I wrote actually doesn't happen that way; however, that's the way it end up and it never knows we took a shortcut. The other point I want to make is that you may use this shortcut ONLY when you are given H^+ and H2CO3 and you CO3^2- OR you are given CO3^2- and H2CO3 and you want to find H^+. It will not work for a given of H2CO3 and you want to find H^+ and/or HCO3^-.)