Consider the Titration of 100

Multiple Choice

Consider the titration of 100.0 mL of the weak diprotic acid H₂A (0.10 M) with 0.20 M NaOH.What are the major species at each of the following points in the titration? (Water is always assumed to be a major species. )
-After 50.0 mL of 0.20 M NaOH is added

A) HA^-
B) H₂A,HA^-
C) HA^-,A^2-
D) H₂A
E) none of these