Answer:
Sodium oxalate is a basic salt. In water it can be dissolved and dissociated.
The oxalic acid in water has two dissociations.
Explanation:
Na2C2O4 ---> 2Na+ + C2O4-2
Sodium oxalate is the conjugate base of a weak acid. In water this salt, dissociates completely giving rise to the sodium and oxalate ions. As Na+ comes from a strong base, in water it does not produce hydrolysis while oxalate does react in water, because it takes a proton from it and it generates a basic hydrolysis releasing OH-.
C2O4-2 + H2O ⇄ HC2O4- + OH-
In water the salt is basic. The pH of an aqueous solution of this salt is basic, since OH- is generated.
The HC2O4- has a second hydrolisis, it takes another proton from water to form oxalic acid.
HC2O4- + H2O ⇄ H2C2O4 + OH-
The oxalic acid acts as a weak acid, it can release 2 protons to water, to make oxalate (its conjugate base).
H2C2O4 + H2O ⇄ H3O+ + HC2O4-
HC2O4- + H2O ⇄ H3O+ C2O4-2
The HC2O4- acts as an ampholyte since it accepts and delivers protons simultaneously.
