CHEM255 Weak Acids and Bases and Polyprotic Acids

Acid dissociation constant (Ka)

the ratio of the concentration of the dissociated form of an acid to the concentration of the undissociated form.

Base association constant (Kb)

the ratio of the concentration of the associated form of a base to the concentration of the undissociated form.

ICE table

Initial, Change, Equilibrium

Percent dissociation

the ratio of the amount of a substance that is dissociated at equilibrium to the initial concentration of the substance in a solution, multiplied by 100.

Polyprotic acids and bases

compounds that can donate or accept more than one proton.

Amino acid structure

• Central carbon atom

• Amino group

• Carboxyl group

• Single hydrogen

• Variable R group

Zwitterion

a molecule that contains charges but is neutral overall. Most often used to describe amino acids.

Amphiprotic

a species that can either accept or donate a proton.