Boltzmann constant and Ek Remember:. pV = nRT Where:. n = number of moles of gas and R = universal molar gas constant. Boltzmann decided it would be useful if we know what the gas constant was per molecule, not per mole. He came up with a new constant - named the Boltzmann constant, of course - which was: Where:. k = the Boltzmann constant R = the universal molar gas constant NA = Avogadro's number, the number of particles in one mole. Then it was possible to rewrite pV = nRT as pV = NkT Where:. N = no of atoms or molecules involved. If you combine and pV = NkT to give or, in words The average Ek of the particles = a constant x temperature (in kelvin). This confirms what we've mentioned a number of times in this section, that the temperature of a gas depends only on the Ek of the molecules that make it up.