416 Mr. W. M. Hicks on some Effects of Dissociation 

 where jo is constant; 





^t+.'S) 



, =1+ x e $ +1+ < 



3 (2^-M^+M+^-i | 



_ 1[2 *§ +1+ ? 



3 (2X 2 -X 1 )^-J +X 1 + (2X 2 -X 1 )r- £ J' 



In the above we have neglected the variation of the poten- 

 tial energy of molecules except in the case where they are 

 broken up. The above formula is greatly simplified if we 

 consider, as is highly probable, that a molecule has twice the 

 number of degrees of freedom of a free atom — in other words, 



2X 2 = Xi; we then get 



3 I dt 



20. If the atoms be smooth and spherical (as has been sup- 

 posed throughout the present paper), any internal energy an 

 atom may have must be unaffected by change of temperature ; 

 and in this case \^ = 2. 



The blow just sufficient to break up a molecule is c ; if this 



acted in the most favourable manner, the work done in sepa- 



c 2 

 rating a molecule would be ^— = 2\6 . Hence I is < 2X0 O . 



If we put I = 2X0o, 



d 



1 + S+0 



2 



c 3 2-2<9 



3 i a d 

 l - 6o dS 



If 6 is small and about 100°, L e. —173° C, we find from 



