Chapter 12, Problem 12.36P

(a)

Interpretation Introduction

Interpretation:

Fraction of $1\text{-naphthoic acid}$ found in form of $\text{HA}$ and ${\text{A}}^{-}$ at $\text{pH}$ 2 has to be calculated.

Concept Introduction:

Formula to compute fraction of an acid in form of $\text{HA}$ is as follows:

  ${\text{α}}_{\text{HA}}=\frac{\left[{\text{H}}^{+}\right]}{\left[{\text{H}}^{+}\right]+K_{\text{a}}}$

Here

$\left[{\text{H}}^{+}\right]$ denotes concentration of $\left[{\text{H}}^{+}\right]$.

$K_{\text{a}}$ denotes ionization constant of acid..

${\text{α}}_{\text{HA}}$ denotes fraction in form of $\text{HA}$.

Formula to compute fraction of an acid in form of ${\text{A}}^{-}$ is as follows:

  ${\text{α}}_{{\text{A}}^{-}}=\frac{K_{\text{a}}}{\left[{\text{H}}^{+}\right]+K_{\text{a}}}$

Here

$\left[{\text{H}}^{+}\right]$ denotes concentration of $\left[{\text{H}}^{+}\right]$.

$K_{\text{a}}$ denotes ionization constant of acid..

${\text{α}}_{{\text{A}}^{-}}$ denotes fraction in form of ${\text{A}}^{-}$.

(b)

Interpretation Introduction

Interpretation:

Fraction of $1\text{-naphthoic acid}$ found in form of $\text{HA}$ and ${\text{A}}^{-}$ at $\text{pH}$ 3 has to be calculated.

Concept Introduction:

Refer to part (a).

(c)

Interpretation Introduction

Interpretation:

Fraction of $1\text{-naphthoic acid}$ found in form of $\text{HA}$ and ${\text{A}}^{-}$ at $\text{pH}$ 3.5 has to be calculated.

Concept Introduction:

Refer to part (a).