kech105 (1)

Gibbs energy change (∆G) is a thermodynamic potential that indicates the spontaneity of a process; a negative ∆G indicates a spontaneous process.

The types of thermodynamic systems include closed, open, and isolated systems.

Entropy is a thermodynamic state function that measures the degree of disorder or randomness in a system and is used to determine spontaneity.

Thermodynamics is concerned with energy transformations and changes in macroscopic systems involving a large number of molecules.

The first law of thermodynamics states that energy cannot be created or destroyed, only transformed from one form to another.

Spontaneous processes occur without external intervention, while non-spontaneous processes require energy input to occur.

The relationship between ∆G and the equilibrium constant indicates that a negative ∆G corresponds to a reaction favoring products at equilibrium.

State functions are properties that depend only on the state of the system, such as internal energy (U) and enthalpy (H).

Chemical energy stored by molecules is released as heat during combustion, and it can also be used to do mechanical work or provide electrical energy.

Hess's law states that the total enthalpy change for a reaction is the sum of the enthalpy changes for individual steps, regardless of the pathway taken.

The laws of thermodynamics apply only when a system is in equilibrium or moves from one equilibrium state to another.

Macroscopic properties like pressure and temperature do not change with time for a system in equilibrium state.

Energy changes in chemical systems can be calculated as contributions from work and heat.