3 



PHYSICAL PROPERTIES AND COMPOSITION 



Substance 



D 



The density at the absolute zero is, therefore, in accord- 

 ance with the position of this temperature as the corre- 



T 



spending temperature , a fairly constant multiple, about 



four times the critical density. This agrees with the results 

 obtained from measurements on pentane at the lowest tem- 

 peratures 1 ; this at 189 has a density of 0-869 approxi- 

 mately (t k = 1 88, D k = 0-235, A) : A- = 4-o8), whilst from 

 the reduced characteristic equation for fluor-benzene (p. 28) 

 we get 



21956 + 



We may add that the characteristic equation employed 

 partly answers to this result, since in 



for T = o, V -b = o, therefore F = b. 



1 Zeitschr. f. Phys. Chem. 23. 371 



