Chapter 14, Problem 14.81SP

Interpretation Introduction

Interpretation:

$\text{pH}$ and percent dissociation of given aspirin (Acetylsalicylic acid) has to be calculated.

Concept Introduction:

$\text{pH}$ is an logarithmic expression to express a solution is acidic, basic or neutral.  The $\text{pH}$ scale has values between $1-14$ and on which $7$ is neutral, below $7$  values are more acidic in nature and above $7$  values are more basic in nature.

$\text{pH + pOH= 14}$

$\text{pH = -log}\left[{\text{H}}_{\text{3}}{\text{O}}^{\text{+}}\right]$

$\left[{\text{H}}_{\text{3}}{\text{O}}^{\text{+}}\right]{\text{= antilog(-pH) =10}}^{\text{-pH}}$

$\text{pOH = -log}\left[{\text{OH}}^{-}\right]$

$\left[{\text{OH}}^{-}\right]{\text{= antilog(-pOH) =10}}^{\text{-pOH}}$

Percent dissociation:

It is defined as concentration of dissociated acid divided by the concentration of the acid times $100\%$.

$\text{Percent}\text{dissociation =}\frac{{\left[\text{HF}\right]}_{\text{dissociated}}}{{\left[\text{HA}\right]}_{\text{initial}}}\times 100\%$