210 Dr. A. Naumann on the Specific Heat of Gases 



constant pressure is made up of 



Heat of atomic motion . . a-=n . 0*034 



Heat of molecular motion . m = 3 . 0*034 



Heat of expansion . . 7'— y— 2. 0*034 



Specific heat . . y = ( w + 5) .0-034 



For any given pressure of p millims. we have the general 

 equation 



,_ (» + 5) Q-Q34.jp 

 7 "~ 760 



§ 2. Comparison of consequences following from the conclusions 

 arrived at with the results of observations of other kinds. 



The correctness of the values above arrived at, and of the 

 views upon which they are based, is capable of being tested by a 

 comparative examination of the values deduced from them of 

 magnitudes forwhich numerical values have already been obtained 

 by observations and reasoning of a different kind. Thus from 

 equations (6) and (7) we obtain, for the ratio of the two specific 

 heats, 



7~n + 3 (8) 



As this value is independent of the magnitude a, if the ratio 

 of the several constituent portions of the specific heat (namely 

 n : 3 : 2) upon which it is based be admitted, it must be absolutely 

 correct. For gases with diatomic molecules, such, for instance, 

 as the permanent gases, we have 



£4=i-4. ....... (9) 



By other methods this quotient has been found = 1*41*. 

 From each of these numbers, by means of the mean empirical 

 specific heat of the permanent gases, the corresponding values 

 of 7'— 7, the heat of expansion, can be found. Thus, on the 

 one hand, 



/ _ 023773 



7 0-23773 — (/— 7) 



on the other hand, 



7' _ 0-23773 



7 ~~ 0-23773- (7' -7) 



= 1-4.5 



= 1-41 



* Clausius, Ann. der Chem. und Pharm. vol cxviii. p. 113 (1861); Ad. 

 Dronke, Pogg. Ann. vol. cxix. p. 393 (1863) ; Zeuner, Grundzuge der 

 mechanischen Warmetheorie, p. 38 (1860). 



