Compounds and Densities of their Solutions. 301 



In conclusion a few words about the densities and molecular 

 volumes. There is no need of putting the data given above 

 into plots. There is no peculiarity in any of them, not even 

 in the aqueous solution of urethane nor in the chloroform 

 solution of chloral hydrate, but the plots showing variation in 

 molecular volume as a solute passes from one solvent into 

 another are instructive. They are given in figure 4. 



^/^ 



CViij 













\ 









! 



\V 









^ 



^ 



s 





V 



^ 





\ 



w 



\ 



J6 z 



3 



















0,H,CH 



\ 



^ 









CMjOH 





\ 



^ 









^ 





?^ 



>v 





10 iO JO ,'r 



f S'O 



ZO 30 



ZO JO 

 SuyC/tA/tUoyUd 



CH,OH 



1 









\ 



i 









\ 









i 









b 



^ 



=^ 



ZO JO 



The formula at the beginning of the horizontal line gives 

 the solvent, and the numbers along the horizontal give the 

 relative volumes of one gram-molecule of solute at the temper- 

 ature stated on the lines. 



For example, the relative volume of one gram-molecule of 

 acenaphthene in chloroform at 10° has been obtained in this 

 way : — 



Solubility of acenaphthene! from solubility curves 16*0^ gram- 



mols. 

 Proportion of chloroforms 84-0 •119-3/ (84-0 • 119-3 -M6-0 • 154). 

 Volume of one gram chloroform at 10° from density curve = 

 1/1 -5 Ice. 

 " " chloroform in one gram of solution is [84-0 •119-3/ 



(84-0 • 119-3 -M6-0^ 154)] l/l-51cc=:0-5327cc. 

 " " one gram of solution at 10° = 1/] -4000. 

 " " acenaphthene in one gram of solution=l/l-40 — 0*5327 



= 0-1811cc. 

 " corresponding to one molecule of acenaphthene = 0*1 8 11/ 16 

 = 0-0113. 



Am. Jour. Sci.— Fourth Series, Yol. XIT, No. 82.— October, 1802. 

 21 



