Max Planck’s Determination of the Avogadro Constant

Abstract

The work leading to the discretization of energy is certainly Max Planck’s most famous work. In addition to quantization, a new universal constant, the Planck constant, was introduced with a new calculation of the Drude-Boltzmann constant. The second part of this work, published separately in 1901, contains the calculation of several important constants in physical chemistry and will be the main objective of the present article. Using the two definitions of entropy, the one introduced by Planck and the one by Boltzmann, the relationship between the constants, R, NA and k was established. Guided by this result. Planck calculates the number of particles per mole, the Loschmidt constant, and the electron charge. In the latter case, Faraday’s constant was used, also known in 1900. Possibly, due to the importance of the first article on the discretization of energy, little study is devoted to this second work. However, much can be discussed and learned by approaching the historical context of this second article, which also serves as a reference for knowing the gas constant, Boltzmann constant, number of particles per cubic centimeter, number of particles per mole, electronic charge and Faraday constant, at the end of the XIX century.