Avogadro's number: interesting information. Where is Avogadro's number used?

Quantity of substanceν is equal to the ratio of the number of molecules in a given body to the number of atoms in 0.012 kg of carbon, that is, the number of molecules in 1 mole of a substance.
ν = N / N A
where N is the number of molecules in a given body, N A is the number of molecules in 1 mole of the substance of which the body consists. N A is Avogadro's constant. The amount of a substance is measured in moles. Avogadro's constant is the number of molecules or atoms in 1 mole of a substance. This constant was named after the Italian chemist and physicist Amedeo Avogadro(1776 – 1856). 1 mole of any substance contains the same number of particles.
N A = 6.02 * 10 23 mol -1 Molar mass is the mass of a substance taken in the amount of one mole:
μ = m 0 * N A
where m 0 is the mass of the molecule. Molar mass is expressed in kilograms per mole (kg/mol = kg*mol -1). Molar mass is related to relative molecular mass by the relationship:

μ = 10 -3 * M r [kg*mol -1 ]
The mass of any quantity of substance m is equal to the product of the mass of one molecule m 0 by the number of molecules:
m = m 0 N = m 0 N A ν = μν
The amount of a substance is equal to the ratio of the mass of the substance to its molar mass:

ν = m/μ
The mass of one molecule of a substance can be found if the molar mass and Avogadro's constant are known:
m 0 = m / N = m / νN A = μ / N A

Ideal gas- a mathematical model of a gas, in which it is assumed that the potential interaction energy of molecules can be neglected in comparison with their kinetic energy. There are no forces of attraction or repulsion between molecules, collisions of particles with each other and with the walls of the vessel are absolutely elastic, and the interaction time between molecules is negligible compared to the average time between collisions. In the extended model of an ideal gas, the particles of which it consists also have a shape in the form of elastic spheres or ellipsoids, which makes it possible to take into account the energy of not only translational, but also rotational-vibrational motion, as well as not only central, but also non-central collisions of particles, etc. )