Molecular Constants
In the kinetic theory of gases, there are certain constants which constrain the ceaseless molecular activity.
A given volume V of any ideal gas will have the same number of molecules. The mass of the gas will then be proportional to the molecular mass. A convenient standard quantity is the mole, the mass of gas in grams equal to the molecular mass in amu. Avogadro's number is the number of molecules in a mole of any molecular substance.
The average translational kinetic energy of any kind of molecule in an ideal gas is given by