Keq

Free energy

Energy that is available to do work.

Reaction Rate

The number of atoms, ions, or molecules that react in a given time to form products.

Activation energy

The minimum energy that colliding particles must have in order to react.

Activated complex

The arrangement of atoms at the peak of an energy barrier.

Equilibrium

A state where the rate of production of reactants equals the rate of production of products.

Equilibrium constant (K_eq) expression

For the reaction C(s) + O2(g) ↔ CO2(g), K_eq = [CO2]/[O2].

Entropy

A measure of the amount of disorder in a system.

Catalyst

A substance that works by lowering the activation energy.

Spontaneous reaction

A reaction that gives off free energy.

Gibbs free-energy change

The change in free energy that indicates if a process is spontaneous or not.

Shifting equilibrium

The change in equilibrium position when conditions such as concentration, pressure, or temperature are altered.

Effect of concentration on reaction speed

Higher concentration increases the number of collisions, making the reaction faster.

Increasing temperature

A factor that causes a reaction to go faster by increasing the number and rate of collisions.

Equilibrium concentrations

Concentration values used to calculate equilibrium constants in a reaction.

Increase in entropy

A condition that favors processes such as melting of ice at room temperature.

Change in Gibbs Free Energy (ΔG) for spontaneous reactions

The numerical value is negative.

Effect of more reactant at equilibrium

The production of more products would occur.

Endothermic reaction

A reaction that absorbs heat, causing a shift towards products when temperature is raised.

Volume decrease effect on gases

Decreasing the volume favors the production of the side with fewer gas molecules.

Enzyme

Another name for the catalysts found in biological systems.