GÜ9 



liioleenlos, of theii- collisions and their temporary aggregations — 

 goes straight to its goal by imagining (see above) all the energy 

 absorbed in the surrounding medium, makes it further acceptable 

 that 4:7)1 would after all have to become simply m. 



But that the theory of the quasi-association can only be of any 

 use in the rarefied gas state, in conjunction with the theory of the 

 colliding molecules, and that the medium theory can be left aside — 

 though there always remain constants undetermined (viz. the associ- 

 ation constants;, as we shall immediately see ; and that this theory 

 entirely fails for more condensed states — this is immediately to be seen. 



For if one would apply the quasi-association theory to liquids, the 

 number of molecules associated to one molecule would theoretically 

 continually increase, so that finally — in the limiting state — the 

 whole liquid mass would have to be considered as one single asso- 

 ciated giant molecule, for which the equation of state of the substance 

 would then lose all its significance, as this is based on the joint 

 action of an exceedingly large number of molecules, and not on a 

 single molecule. What for larger volume can therefore be taken as 

 the equation of state of the whole mass of the substance, would now 

 have passed to the equation of state of a single giant molecule. But 

 in this the separate molecules can again be taken as unities {real 

 association excluded of course) in consequence of the very slight 

 mutual distances (just as for a solid substance), and the equation of 

 state resulting from this will have analogous meaning as the original 

 one, which holds for the gas state. Only we "shall then have to take 

 into account the continual change of the number of degrees of freedom. 



The theory of quasi-association, applied to condensed states, would 

 therefore lead to great contradictions. While the molecules practi- 

 cally behave as single ones, the said theory would lead to an infinite 

 complexity in one giant molecule, with abolition of the original equation 

 of state. 



While VAN DER Waals, therefore, thought he could chiefly explain 

 the deviations of the liquid state with respect to the ideal equation 

 of state by the association theory, we see that exactly in this state 

 this theory would lead to contradictions. It mtiy only be applied in 

 the rarefied gas state, though just there it is not necessary as an 

 explanation of the lieviations from tlie equation of state meant by 

 VAN DER Waals, which would make their appearance not before 

 the liquid state, but which as we saw in the foregoing articles caa 

 be explained also without the assumption of quasi association. It is 

 indeed necessary, however, as we shall see presently, to explain 

 that then 4/n can become m. 



