Theory of Molecular Volumes. 



445 



The contractions are all smaller than in the Aromatic Series, 

 the mean being —12*8 instead of — 15*0. This is due to 

 the increase volumes of the extra hydrogen. We thus have 

 in the following diagrams an attempt to indicate this 

 difference. 



R 



'' c \ 

 / / \ \ 

 ■ CH CHJ 



i 1 II ! 



■CH CH 

 \ % / / 



E. H 



,' C \ 

 / / \ \ 



n-fCH ch-vh 



i I | ; 



H-VCH. CH-fH 



\ \ / / 

 ^ CH / 





H 



Aromatic. 



Hydroaromatic. 



means of a formula 





"b.p. 



'+*(>-&) 



it is possible to calculate the volumes of compounds at the 

 B.P. to a close approximation, especially if we know the 

 volumes of related compounds. Thus Cymene C 10 H U gives 

 us the means of calculating the volumes of all the reduction 

 products thereof, including the single ringed terpenes. 



Cymene, C 10 H 14 

 d 0-8718 d BV 0-7248 (Sclriff). 



-^ = 1'2028 



<*B.P. 



B.P. = 17G-2 (449-2 A). 



27: > > 273 



1_ —1— — ■'■W? 



B.P. 449-2 ~~ 



Ratio (const.) K= .^q 9 - =0*52. 



