Question

The image given represents the titration of a $25.0mL$ of an unknown diprotic acid with $0.100MNaOH$.

What is/are the species present at the point of the titration curve indicated by the black arrow?

• A. $H_{2}A$
• B. $H{A}^{-}$
• C. $A^{2-}$
• D. $H_{2}A$ and $H{A}^{-}$

Answer 1

The correct option is B $H{A}^{-}$

Titration is used for determining how much of an analyte in moles (or millimoles) is in a solution. The analyte is the term for the dissolved unknown in the titration experiment. This is done by slowly adding a standard solution, or a reagent of known concentration until the titration is determined to be complete.

complete acid titration

$H{A}^{-}$ is the right choice