Answer: Two.
Explanation: Number of ionization constants associated with an acid equals to the number of hydrogen ions(protons) that it produces in aqueous solution.
For example, HCl is a monoprotic acid as it produces only one hydrogen ion in aqueous solution and so only one ionization constant is associated with it.
[tex]H_2SO_4[/tex] (sulfuric acid) is a diprotic acid as it produces two hydrogen ions in aqueous solution and hence there are two ionization constant values associated with this.
Similarly, Oxalic acid is also a diprotic acid and so two ionization constant values are associated with this.
The two ionization equations of oxalic acid are as follows:-
[tex]H_2C_2O_4\rightleftharpoons H^++HC_2O_4^-[/tex]
[tex]HC_2O_4^-\rightleftharpoons H^++C_2O_4^-^2[/tex]
[tex]Ka_1[/tex] and [tex]Ka_2[/tex] are the two ionization constants for first and second equations respectively.
