Lecture 16 Quantifying Solution Acidity and pH Calculations

Flashcards covering key vocabulary and concepts related to quantifying solution acidity, pOH, ionization, and pH calculations for strong and weak acids.

pH = 7

neutral solution at 25 °C

pH < 7

acidic solution at 25 °C

pH > 7

basic solution at 25 °C

pOH

–log[OH–]eq

pKa

–logKa

pKb

–logKb, etc.

Neutral solution

[H+]eq = [OH–]eq

Acidic solution

[H+]eq > [OH–]eq

Basic solution

[OH–]eq > [H+]eq

Percent Ionization of an Acid (HA)

the percentage of added acid molecules that actually dissociate into H3O+ and anion (A–)

Calculating the pH of STRONG Acid Solutions

calculate [H3O+] from the complete dissociation of the acid, neglect the contribution of [H3O+] from the autoionization of water unless the strong acid is very dilute (≈ 10–5 M or less)

Calculating the pH of WEAK Acid Solutions

calculate [H3O+] from the partial dissociation of the weak acid by using an ICE table and the Ka of the acid, typically neglect the contribution of [H3O+] from the autoionization of water