You would never hear the unit dozen, terrible, ream, or scores to express the quantity of articles. The quantity of particles is communicated in units of moles. Unit is currently communicated as the quantity of moles of standard Tikel (iotas, particles, or particles) in a substance. Masters concur that one mole of a substance containing the same number of particles with the quantity of particles in 12.0 grams of C-12 isotope that is 6.02 x 1023 particles. Molecule number is called Avogadro's number (NA = Avogadro's Number) or in German Numbers Loschmidt (L).