Attraction of Mass, and some New Gas Equations. 83 

 If T<273, 



n 



1 



1 



vt — Pt t'o 



1 



1 



.T 



T 



= 273 A ' 

 T 



= 1, 

 _R 



n. ft 



Reduced to 



T ' 



y- 273/5, 



u , 0°, and II 

 1 



- 273' ^ 

 R.T 





273 ' 



f -/V 



and in both cases v Q is the experimental value. 



Note. — It is evident that for gases with T > 273 the total 

 pressure is inversely proportional to the reduced " free 

 space." 



If n i .«. y S = latO°C, 



then for the same pressure TL 1 



IIx . n . j3 T = -jfTj a ^ a temperature T >273, 



n . /3 and n . /3 T being " free spaces." J3t is a definite fraction 

 of /3 dependent on T, and /3 has an absolute value expressed 

 in v = l at n o =l. 



The number of molecules with the free space n . /3 T is 



(273\2 

 -m— ) times the number of molecules with the free space 

 ' . /273\ 2 /273\ 



n . (3 , and their co-volume is I -pp- J . ft or ( -^- 1 /3 T . 



Hence expressing its volume in respect of v = l at which 



273 

 it would exert a pressure II T — ^- } the gas. at the tempe- 

 rature T exerts a pressure inversely 'proportional to the 

 volume j i. e. 



n= 273/T . 



n . £ T * 

 But if we express that volume n . £t in respect of the 



273 

 volume -7^- at which the gas exerts the pressure n =l, we 



find the total pressure inversely proportional to the reduced 

 free space. Thus we found e. g. for the critical state: 



273 



n c .2/3T e =-p, 



-*-c 



G2 



