Laics of Molecular Force. 235 



internal virial includes the actions between the parts of the 

 molecules as well as those between the molecules. Calling 

 these actious the chemic force, we can write the theorem 

 thus : 



&pv = the total kinetic energy— chemic virial —virial of 

 molecular forces. 



Now in the usual treatment of the equation it is assumed 

 that the chemic virial is equal to that part of the total kinetic 

 energy which is due to the motion of the parts of the mole- 

 cules relatively to their centres of mass, and neutralizes it in 

 our equation, reducing it to 



&pv == translatory kinetic energy of molecules as wholes 



—virial of molecular forces. 



But if we retain the full equation, and assume that the virial 

 term we have been finding for various bodies is the true virial 

 of the molecular forces, and includes none of the chemic virial, 

 then the term usually regarded as the translatory kinetic 

 energy of the molecules as wholes is really the total kinetic 

 energy minus the chemic virial. 



Let E be the total kinetic energy of unit mass, V the virial 

 of the chemic forces, and P their potential energy 5 then, above 

 the critical volume, 



E-V =i ET(l + ^) 



and 



2k 



^(E-V)=|R(l + ^), 



which in the limiting gaseous state becomes 3R/2. 

 Abo 



^ (B-P) = K„, 



the specific heat at constant volume. 

 Below the critical volume, 



i_r- i nfi(i + .-^..J55) > 



|,(E-V)=|E' + |E^.|- ; 



and, again, 



|p(E-P)=K„. 

 R2 



