332 



Albert P. Mathews 



TABLE i 



From Table i it is clear that the number of valences 

 computed from the molecular cohesion is very close to the 

 theoretical number, if one of the oxygen atoms is quadri- 

 valent. The only cases in which fewer valences were found 

 were methyl isobutyrate and methyl propionate. In the 

 former, the computation of "a" may not be exactly right 

 as elsewhere pointed out, the isocompounds always giving a 

 value for "a" a little low as compared with the normal. It 

 is, of course, possible that in them the oxygen is bivalent. 



Table 2 contains some other oxygen compounds which 

 associate and may be supposed on that account to have 

 quadrivalent oxygen. 



In Table 2 the alcohols probably associate somewhat 

 at the critical temperature and acetic acid also; the number of 

 valences, given in the table as computed, were computed 

 with the normal molecular weight and they are, accordingly, 

 too many. It is impossible to determine the total number 

 of valences per molecule by this method for these substances 

 until the average molecular weight has been independently 

 determined at the critical temperature. Of the other sub- 

 stances: acetone, anisol, phenetol, nitrobenzene, acetic anhy- 

 dride, ethyl diacetate and methyl propyl ketone appear to 

 have tetravalent oxygen. The method, however, is not 



