Gibbs energy differential

The fundamental thermodynamic relations are fundamental equations which demonstate how important thermodynamic quantities depend on variables that are measurable experimentally.

Notation:

  1. \(d\) denotes an exact, path-independent differential.

Notes:

  1. Temperature, pressure, and particle count are so called natural variables of Gibbs energy as a thermodynamic potential.

  2. For a system with more than one type of particles, the last term can be represented as a sum over all types of particles, i.e. \(\sum_i \mu_i \, d N_i\).

Conditions:

  1. The system is in thermal equilibrium with its surroundings.

  2. The system is composed of only one type of particles, i.e. the system is a pure substance.

Links:

  1. Wikipedia.

gibbs_energy_change

Infinitesimal change in Gibbs energy of the system.

Symbol:

dG

entropy

Entropy of the system.

Symbol:

S

temperature_change

Infinitesimal change in temperature of the system.

Symbol:

dT

Latex:

\(dT\)

Dimension:

temperature

volume

Volume of the system.

Symbol:

V

pressure_change

Infinitesimal change in pressure inside the system.

Symbol:

dp

chemical_potential

Chemical potential of the system.

Symbol:

mu

Latex:

\(\mu\)

particle_count_change

Infinitesimal change in the number of particles in the system.

Symbol:

dN

law

dG = -1 * S * dT + V * dp + mu * dN

Latex:
\[dG = - S \, dT + V \, dp + \mu \, dN\]