Theory of Molecular Volumes. 751 



these, we obtain the value oi" the correction for want of 

 symmetry by difference. 



This apparently depends on the square of the number of 

 atoms at least for compounds of the type R — R/ = OH 2 . 



The correction is 



A, = -((m + 5) x n oM x 0'003, 



and the whole formula is 



V m =(6y i + 5)[3-664 + 0'010l(|-2)(|-l)-0 



00 



o n, 



By means of this formula, compounds of the type R — R' = 

 (symmetrical) and those of the type R — R' = CH 2 (unsym- 

 metrical) may have their volumes at the normal B. P. 

 calculated. 



Calculation of the Volumes of the Symmetrical and 

 Unsymmetrical Compounds. 



Class. 



Compounds. 



W. 



n. 



V/W. 



Corr. for 

 want of 



V/W 

 calc. 



V/W 

 obs. 



V calc. 



V obs. 













Symmetry. 







S 



CH, .O.CH, ... 



17 



2 



3664 





_____ 



3-677 



62-25 



62-56 



u 



CH., .O.C.,H- ... 



23 



3 



3661 



-0-009 



3-652 



3-652 



S4-0 



84-0 



s 



C..U. .O.ClH- ... 



29 



4 



3-6G4 





3-664 



3-664 



106-25 



106-2 



u 



C.^H. .O.C^H- ... 



35 



5 



3-672 



- 0-015 



3-657 



3-659 



128-00 



128-08 



s 



c 3 h 7 . O . C,Ul ... 



41 



6 



3-684 





3-684 



3-689 



151-04 



151-27 



u 



C 3 H..O.C 4 H 3 ... 



47 



7 



3-705 



-0-021 



3-684 



3-686 



173-15 



173-25 



s 



CH,',. 0.0,11,, ... 



53 



8 



3-725 





3-725 



3-730 



197-42 



197-72 



u 



C-'H,! .0.0,11, ... 



59 



9 



3752 



-0-027 



3-725 



3-733 



219-77 



22035 



s 



C.H^O.C-H;, ... 



65 



10 



3-785 





3-785 



3-789 



246-02 



246-28 



u 



5 H n • . egg: ■ 



71 



11 



3-823 



-0-033 



3-790 



3795 



269-09 



269-44 



s 



C.H^.O.C.H,.... 



77 



12 



3-S66 





3-866 



3-867 



297-68 



297-76 



u 



C.H^ . . C 7 E 15 ... 



S3 



13 



3-914 



-0 039 



3'875 



3-870 



321-62 



321-21 



8 



O-H^.O.O-H,... 



89 



14 



3-967 





3-967 



3-970 



353-06 



353-42 



u 



C T H 15 .O.C b H 17 ... 



95 



15 



4-025 



-0-045 



3-980 



3-975 



378-1 



377 "6 



We have supposed, as is usual, that these variations are due 

 to symmetry or want of it, hut this explanation does not seem 

 to be complete or even quite satisfactory. A more precise 

 knowledge of the inner meaning- of this constitutive variation 

 may be eventually arrived at. This also applies to the 

 meaning of the effect of variation with complexity. 



