BY MEANS OF CATALYSTS CREIGHTON. 7 



a pure acid. The impure acids were twice recrystallised from 

 water at 60°. lu agreement with Fajans, the melting points of 

 the d- and 1- acids were 127° — 128° ; while that of the 

 inactive acid was higher, 136° — 137°, from which it may be 

 concluded that the acid, prepared as above, is a racemic acid. 

 Analysis by titration with barium hydroxide solution and 

 phenolphthalein gave the following degrees of puritv: 



d - acid 1-acid in -acid 



I 100,07^ I 100,12^ I 100,07^ 



II 100,11^ II 99,88^ II 100,10,^ 



III 99,78^ III 99,98^ III 



Mean: 99,99^ 99,99^' 100,09^ 



The optical rotation of these camphor-carboxylic acids was 

 determined a.t 25° : 



3.7743 g. d- acid, dissolved to 25 ccm. in absolute alcohol, 

 gave a rotation of +23°. 02 in a 2.5 dcm. tube. 



0.4302 g. 1- acid, dissolved to 10 cc. in absolute alcohol, 

 gave a rotation of -2°. 63 in a 1 dcm. tube. 



These rotations correspond to a specific rotation of ± 61°.l. 



The acid prepared from the inactive camphor was com- 

 pletely inactive. 



Besides -these tests of purity the aflSnity constant of the 

 d- and 1- acid was measured, and the results obtained at 



2.5° are 



given 



below^ : 













d- Catnplior carboxylic 

 acid. 

 Mol. Degree 

 V lit. Cond. Diss. 



I 100 }- 



100 k 



= 374 

 V lit. 



1 — Camphor-carboxylic 



acid. 

 Mol. Degree 

 Cond. Diss. 



/ 100 V 100 k 



31,32 



26,56 



7,10 



0,0173 



31,32 



26,60 



7,11 



0,0174 



62,64 



36,96 



9,88 



0,0173 



62,64 



37,65 



10,07 



0,0180 



93,97 



44,92 



12,01 



0,0175 



156,64 



57,65 



15,41 



0,0174 



156,61 



57,63 



15,41 



0,0179 



250,49 



70,24 



18,78 



0,0173 



250,58 



70,91 



18,96 

 Mean : 



0,0177 



814,35 



117,21 



31,34 

 Mean : 



0,0176 





0,0175 



0,0175 



1. One lialf of the specific conductivity of the water was subtracted 

 from that obtained for the solution. In the case of the d- acid J. 4 X 10 , 

 and in the case of the 1- acid 1. 2.7 X lO"*. 



