Graham's law has come to denote an important class of finely divided materials. Around the time Graham did his work, the concept of molecular weight was being established largely through the measurements of gases. Daniel Bernoulli suggested in 1738 in his book Hydrodynamica that heat increases in proportion to the velocity, and thus kinetic energy, of gas particles. Italian physicist Amedeo Avogadro also suggested in 1811 that equal volumes of different gases contain equal numbers of molecules. Thus, the relative molecular weights of two gases are equal to the ratio of weights of equal volumes of the gases. Avogadro's insight together with
Noro–Frenkel law of corresponding states thermodynamic variables that describe an equation of state (temperature, pressure, and volume) with respect to their values at the liquid-gas critical point, all simple fluids obey the same reduced equation of state. Massimo G. Noro and Daan Frenkel formulated an extended law of corresponding states that predicts the phase behaviour of short-ranged potentials on the basis of the effective pair potential alone – extending the validity of the van der Waals law to systems interacting through pair potentials with different functional forms. The Noro–Frenkel law suggests to condensate the three quantities which are expected to play a role in the