Chapter 16, Problem 16.5P

Interpretation Introduction

Interpretation:

The cell voltage at titrant volumes of $\text{1}\text{.0}\text{mL}$, $\text{7}\text{.5}\text{mL}$, $\text{14}\text{.0}\text{mL}$, $\text{15}\text{.0}\text{mL}$, $\text{16}\text{.0}\text{mL}$, and $\text{30}\text{.0}\text{mL}$ has to be calculated. Titration curve has to be computed.

Concept Introduction:

Titration is an analytical method of quantitative chemical analysis to determine concentration of analyte. A reagent known as titrant is prepared as standard solution of known concentration and volume.

Redox reaction is a reaction that includes change in oxidation number of molecule, atom or ion and these changes are due to transfer of electron from one species to another. A complete reaction involves oxidation and reduction.

Nernst equation in electrochemistry is the equation that relates the reduction potential of a reaction to the standard reduction potential value.

Consider a hypothetical reaction as follows:

    $\text{Ox}+{\text{ne}}^{-}\to \text{Red}$

Expression to compute $E_{\text{cell}}$ as per the Nernst equation is written as follows:

  ${\text{E}}_{\text{cell}}={\text{E}}^0-\frac{\text{RT}}{\text{nF}}\text{ln}\frac{{\text{a}}_{\text{Red}}}{{\text{a}}_{\text{Ox}}}$

Here,

$E_{\text{cell}}$ denotes overall cell potential.

$E_{\text{cell}}^{°}$ denotes standard cell potential.

$n$ is moles of electrons transferred in each reaction.

$\text{R}$ is  universal gas constant.

$\text{T}$ is temperature of interest in Kelvin scale.

${\text{a}}_{\text{red}}$ is activity of the reduced form.

${\text{a}}_{\text{ox}}$ is activity of the oxidized form.