Ch 16 chem

Flashcards covering key concepts, terms, and principles from the lecture on chemical thermodynamics.

Thermodynamics

The study of the relationship between heat and work, determining possible processes.

Spontaneity

Indicates whether a process can occur without external assistance.

Entropy (S)

A measure of the distribution of energy in a system; reflects disorder.

Free energy (G)

Relates enthalpy and entropy to spontaneity; can indicate equilibrium constants.

Enthalpy change (ΔH)

The heat content change of a system during a process.

Activation energy (Ea)

The minimum energy required to initiate a chemical reaction.

Second Law of Thermodynamics

States that the total entropy of an isolated system can never decrease over time.

Microstate

A specific arrangement of a system's components that can lead to different energy distributions.

Standard Molar Entropy (S°)

The entropy of one mole of a substance in its standard state.

Third Law of Thermodynamics

States that the entropy of a perfect crystal approaches zero as the temperature approaches absolute zero.

Free Energy Change (ΔG)

Indicates if a reaction will occur spontaneously; ΔG < 0 means spontaneous.

Chemical potential

The change in free energy associated with the process; influenced by reactants/products.

Equilibrium Constant (K)

Describes the ratio of concentrations of products to reactants at equilibrium.

Non-spontaneous Process

A process that cannot occur without external intervention.

Spontaneous Process

A process that occurs without continuous external action.

Entropy Change (ΔS)

The difference in entropy between two states.

Gibbs Free Energy

Defined as ΔG = ΔH - TΔS, representing the free energy of a system at constant temperature and pressure.

Exothermic processes

Reactions that release heat into the surroundings.

Endothermic processes

Reactions that absorb heat from the surroundings.

Thermodynamically favored reaction

A reaction that favors the formation of products under certain conditions.

If delta H is negative and delta S is positive then what happens with temperature

Spontaneous at both low and high temperatures

If delta H is positive and delta S is negative then what happens with temperature

Non spontaneous at both low and high temperatures

If both delta H and delta S are negative what happens to temperature

Spontaneous at low temperature and non spontaneous at high temperatures

If both delta H and delta S are Positive what happens With temperature

Non spontaneous at low temperature and spontaneous at high temperatures