Acid-Base Equilibrium and Buffer Solutions

These flashcards cover key concepts related to acid-base equilibrium and buffer solutions in chemistry.

Bronsted-Lowry Acid

Any species capable of donating a proton.

Bronsted-Lowry Base

Any species capable of accepting a proton.

Arrhenius Acid

Compounds that increase the concentration of hydrogen ions (H+) in solution.

Arrhenius Base

Compounds that increase the concentration of hydroxide ions (OH–) in solution.

Conjugate Acid

The species formed when a Bronsted-Lowry base accepts a proton.

Conjugate Base

The species left over after a Bronsted-Lowry acid donates a proton.

Amphoteric

A substance that can act as both an acid and a base.

Self-Ionization of Water

The reaction in which water donates a proton to another water molecule, forming hydronium and hydroxide ions.

Water Ionization Constant (Kw)

The equilibrium constant for the self-ionization of water, equal to 1.0 x 10−14.

pH

A measure of the hydrogen ion concentration in a solution, defined as pH = -log[H+].

Henderson-Hasselbalch Equation

An equation that relates the pH of a buffer solution to the pKa and the concentrations of the conjugate base and acid.

Buffer Solution

A solution that resists changes in pH when small amounts of acid or base are added.

Acid Dissociation Constant (Ka)

A measure of the strength of an acid in solution.

pKa

The negative logarithm of the acid dissociation constant (Ka); pKa = -log(Ka).

Equilibrium Reaction

A state in which the rates of the forward and reverse reactions are equal.

Le Chatelier's Principle

If an outside change is applied to a system at equilibrium, the system will shift to counteract the change.

Hydronium Ion

The ion formed when a water molecule gains a proton (H3O+).

Hydroxide Ion

The ion formed when a water molecule loses a proton (OH−).