Question

The titration of an acid (H2A) with LiOH solution generates the following titration curve. What are the main components (more than half of the initial amount of H2A, besides H2O) at equivalence point 1 (EP1) and equivalence point 2 (EP2)?
Main Components at EP1 Main Components at EP2
A H2A and OH− A2− and OH−
B HA− and Li+ A2− and Li+
C HA− and OH− HA− and Li+
D H2A and Li+ HA− and OH−

Answer 1

Answer:

B) HA⁻ and Li⁺ A²⁻ and Li⁺

Explanation:

Titration of acid H₂A with LiOH solution.

At first equivalent point

    H₂A + LiOH → HA⁻ + Li⁺ + H₂O

    Main component at (EP1) => HA⁻ and Li⁺

At second equivalence point

    HA⁻ + LiOH → A²⁻ + Li⁺ + H₂O

    Main component at (EP2) => A²⁻ and Li⁺

Therefore, the correct answer is B