Question

When we add titrate sodium carbonate solution (in beaker) with hydrochloric acid, we observe various results. Match list I with list II.

Answer 1

When we add titrate sodium carbonate solution (in beaker) with hydrochloric acid, we observe the following:
(A) At the start of titration, hydrolysis of $C{O}_3^{2-}$ occurs.
(B) Before the first equivalent point, buffer solution of $HC{O}_3^{-}$ and $C{O}_3^{2-}$ is obtained.
(C) At the first equivalent point, amphiprotic anion is obtained with $pH=1/2(p{K}_{a1}+p{K}_{a2})$.
(D) Between the first and second equivalent points, buffer solution of $H_{2}C{O}_3$ and $HC{O}_3^{-}$ is obtained.