Combined Study Guide: Chemical Equilibrium & Acid-Base Chemistry

These flashcards cover key vocabulary terms and definitions related to chemical equilibrium and acid-base chemistry from the combined study guide.

Dynamic Equilibrium

The state where the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products.

Kinetics

The study of reaction rates; characterized by the rate constant (k) which determines how fast a reaction reaches equilibrium.

Equilibrium Constant (K)

A constant that indicates the extent of a reaction; how much product is present at equilibrium.

Reversible Reaction

A reaction that can reach dynamic equilibrium, indicated by the symbol $<br /> ightleftharpoons$.

Mass Action Expression (Q or K)

An expression that shows the ratio of concentrations of products to reactants raised to the power of their coefficients.

Q vs. K

Q is the reaction quotient calculated at any time; K is the equilibrium constant calculated at equilibrium.

Le Chatelier’s Principle

A principle stating that if a system at equilibrium is subjected to a change, the system will adjust to counteract that change.

Acid-Base Theory (Brønsted-Lowry)

A theory defining acids as proton donors and bases as proton acceptors.

Conjugate Acid-Base Pair

Two species that differ by one proton (H+).

Amphiprotic

Substances that can act as either an acid or a base.

Ion Product of Water (Kw)

At 25 °C, $K_w = [H_3O^+][OH^-] = 1.0 imes 10^{-14}$.

pH

A measure of the acidity or alkalinity of a solution, calculated as $pH = - ext{log}[H_3O^+]$.

Percent Ionization

Calculated as the equilibrium concentration of ionized acid divided by the initial concentration of the acid, multiplied by 100%.

ICE Table

A table used to organize the initial concentrations, changes in concentrations, and equilibrium concentrations of reactants and products.

Oxoacids

Acids that contain oxygen, with strength increasing with more oxygen atoms or a more electronegative central atom.

Strong Acids/Bases

Substances that ionize completely in solution, leading to equal concentrations of H3O+ or OH- as the acid or base.

Weak Acids/Bases

Substances that only partially ionize in solution; strength is determined by their Ka or Kb values.

Catalysts

Substances that increase the rates of both forward and reverse reactions without changing the equilibrium position or the value of K.

pOH

A measure of the hydroxide ion concentration, calculated as $pOH = - ext{log}[OH^-]$.

Equilibrium Calculations

Calculations involving the use of initial concentrations, changes in concentrations, and equilibrium concentrations in a chemical equilibrium context.

Buffer Solution

A solution that resists changes in pH when small amounts of acid or base are added, usually composed of a weak acid and its conjugate base.