What is Number of particles: Definition and 25 Discussions

The particle number (or number of particles) of a thermodynamic system, conventionally indicated with the letter N, is the number of constituent particles in that system. The particle number is a fundamental parameter in thermodynamics which is conjugate to the chemical potential. Unlike most physical quantities, particle number is a dimensionless quantity. It is an extensive parameter, as it is directly proportional to the size of the system under consideration, and thus meaningful only for closed systems.
A constituent particle is one that 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). For example, for a thermodynamic system consisting of a piston containing water vapour, the particle number is the number of water molecules in the system. The meaning of constituent particle, and thereby of particle number, is thus temperature-dependent.

In Particals consist (Ions, molecules, electrons, atom, compound etc.)

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  1. S

    A How does the number of particles increase the surface adsorption?

    How the number of the particles in a solution increase the probability to get adsorption on a surface? which physical terms explain this? For example when I increase the concentration of molecules in a solution I can see that the adsorption and the aggregation on the surface happen.
  2. F

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  3. L

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  4. L

    A How to choose the number of particles per site in Fermionic DMRG?

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  5. Ericdjs

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  6. G

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  7. E

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  8. R

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  9. E

    I Energy of a number of particles

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  13. Stephanus

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  14. N

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  15. C

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  16. N

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  17. J

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  18. T

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  19. J

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  20. S

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  21. S

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  22. J

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  23. E

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  25. L

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