Chapter 11, Problem 11.70P

Interpretation Introduction

Interpretation:

The family of graphs for the titration $\text{50}\text{.0}\text{mL}$ of $\text{0}\text{.0200}\text{M}{\text{H}}_{\text{2}}\text{A}$ with $\text{0}\text{.100}\text{M}\text{NaOH}$ has to be plotted.

Concept Introduction:-

Titration of diprotic acid with strong base:

When a strong acid is titrated against diprotic acid, there is an equivalence or stoichiometric point, when an H⁺ is dissociated then there are multiple equivalence points. The equivalence point will occur when the moles of the strong base added to same amount of the moles of weak acid present. However, when a weak polyprotic acid is titrated. Therefore, the number of equivalence points depends on the number of H⁺ atoms that can be removed from the molecule.

Spreadsheet Equation for titration of diprotic with strong base.

$\varphi \equiv \frac{{\text{C}}_{\text{b}}{\text{V}}_{\text{b}}}{{\text{C}}_{\text{a}}{\text{V}}_{\text{a}}}\text{=}\frac{{\text{α}}_{\text{A}}\text{-}\frac{\left[{\text{H}}^{\text{+}}\right]\text{-}\left[{\text{OH}}^{\text{-}}\right]}{{\text{C}}_{\text{a}}}}{\text{1+}\frac{\left[{\text{H}}^{\text{+}}\right]\text{-}\left[{\text{OH}}^{\text{-}}\right]}{{\text{C}}_{\text{b}}}}$

Where,

${\text{C}}_{\text{a}}$=initial concentration

${\text{C}}_b$=final concentration

${\text{V}}_{\text{a}}$=volume of the acid

${\text{V}}_{\text{b}}$= volume of the base

${\text{α}}_{\text{A}}$ =acid dissociation constant.

$\varphi$ =fraction way to equivalence point.