Particle number

From Wikipedia, the free encyclopedia

Conjugate variables
of thermodynamics
Pressure Volume
(Stress) (Strain)
Temperature Entropy
Chem. potential Particle no.

The particle number, N, is the number of so called 'elementary particles' (or elementary constituents) in a thermodynamical system. The particle number is a fundamental parameter in thermodynamics and it is conjugate to the chemical potential.

By calling a constituent element, we state that it cannot be broken into smaller pieces at the scale of energy k·T involved in the process (where k is the Boltzmann constant and T is the temperature). Our definition of elementary particle is thus temperature dependent.