Let’s imagine an ideal gas, for example hydrogen, contained in an enclosure of volume V, which has a temperature T and pressure P on it. With the aim of anlizar the Atomic radius of the hydrogen with the average speed of the molecules, I will then the next development: starting from PV = nRT, m.a.m by dividing by the number of Avogadro N: PV/N = nRT/N, the term V/N = C, would be the apparent volume of a molecule if we sneer at the average distance between these: PC = nKT, where K = R/NBoltzman constant. If concideramos the Atomic volume, C/2 = Q, where Q is the volemen of an atom of hydrogen, therefore PQ = nKT/2. Clearing T, T = 2PQ/nK. Taking into account the equation of the kinetic-molecular theory for gases: T = u * 2. M/3R, u * 2 is the average molecule cuadratica speed and M is the molar mass. Equating T of the two latest equations: u2.M/3R=2PQ/nK; solving and simplifying is: u * 2. m/P = 6Q.

The orbital of an atom of hydrogen is of spherical symmetry, so Q = 4 (pi) r * 3/3. Replacing: u * 2. m/P = 8 (pi) r * 3, where m is the unit mass of a proton, and r is the RADIUS Atomic of spherical symmetry (for quantum level n = 1). Clearing is r: r=(u*2.m/8(pi)P)*(1/3), which allows to calculate the RADIUS Atomic as a result of the average speed of the gas. These results allow us to say that, depending on the State energy of particles may be variations in the relative distances electron-proton in the atom of hydrogen, i.e. energy of the orbital is not constant, but it varies depending on the State thermal and kinetic of its neighboring molecules.