Chemistry. — "Investü/alion.^ on Pastkur's Principle concern,ing the 

 Relation between Molecular and Cri/stallonomical Dissijinmetry : 

 Vl/J. On the spontaneous Fission of racemic Potassium- 

 Cobalti- Oxalate into its optically-active Antipodes." By Prof. 

 F. M. Jakger and William Thomas. B. Sc. 



(Communicated in the meeting of Nov. 30, 1918). 



§ 1. As a continuation of the fissions, accomplished up to this 

 date, of the racemic complex trioxalates of potassium and the triva- 

 lent metals : chromiuia ^), rhodium -), and iridium '), — it appeared 

 desirable to make an attempt to separate the analogously built 

 potassium-cobalti-oxalate: K^\Co{C^O^)^\ -\- 'S^H^O, into its optically- 

 active components for the purpose of a comparison of their 

 rotatory dispersion and crystal-forms. The series of the complex 

 oxalates investigated, would then be really complete. The proposed 

 separation into its antipodes Avas, however, hindered till now by a 

 number of difficulties of various kinds, partially caused by the salt 

 being not very I'esistant towards an increase of temperature, 

 and on the other hand by its particular solubility-relations, when 

 combined with active bases; moreover a troublesome circumstance 

 was its sensitiveness to light-radiation, this causing a rapid decom- 

 position of these salts in solution, under for»nation of a pale pink, 

 hardly soluble preci[)itate, — a reaction, the study of which is now 

 started in our laboratory. 



The racemic salt: /VjjC'KC'jOjjl + 3^ //,(> has been studied by 

 CoPAUX *). It has, like the corresponding salts of the other metals, 

 triclinic symmetry, but it is not isomorphous with them, as follows 

 already from the deviating content of water of crystallisation : while 

 the iridium- and rhodium-ae^ha contain 4.^ molecules of water, the 

 corresponding chromi-s&\t has three, the cobalti-salt 3^ molecules of 

 it. The salt was prepared in the following way in greater quantities. 



A mixture of 25 grammes of cohalti-carbonate, 250 ccm of a satu- 



1) A. Werner, Ber. d. d. Chem. Ges. 45. 3061. (1912). 



2) A. Werner, Ber. d. d. Chem. Ges. 47. 1954. (1914); F. M. Jaeger. Proceed. 

 Ak. V. Wet. Amsterdam, 20. 263. (1917). 



3) F. M. Jaeger, Proceed. Kon. Akad. v. Wet. Amsterdam, 20. 273. (1917); 

 21. 203. (1918). 



•*) H. CoPAUx, Bull, de la Soc Min. 29. 75. (1906); Ann. de Chim. et Phys. 

 (8). 6. 508. (1905). 



