Chemistry. — “The Photochemical Decomposition of Potassium- 
cobaltiovalate and its Catalysis by Neutral Salts” by Prof. 
F. M. Jagger and G. Bereer. | 
(Communicated at the meeting of May 29, 1920). 
§ 1. With the intention of studying the photochemical action of 
dextro- and laevogyratory circularly polarized light upon both optical 
antipodes') of potassiwm-cobalti-ovalate: K, {Co (C,O,),} + 3 H,O, and 
with the purpose of proving the probable difference in speed of 
reaction with each component, if attacked by circularly polarized 
light of opposite direction, — we started a series of experiments, 
which were of a preliminary character as regards the specific 
peculiarities of the photochemical process itself. 
Simultaneously we tried to find out, if it would be possible to 
regulate the speed of reaction by the addition of certain substances to 
the solution in such a way that the velocity became as favourable as 
possible to the purpose aimed at on starting these experiments. We give 
already here a review of the results obtained, which must be con- 
sidered as the foundation of further investigations, because we found 
some remarkable facts, which in their turn might be of interest as 
startingpoints to some other research-work of a more general character. 
If all details are, for the moment, left aside, we can say that the 
photochemical decomposition of the complex potassium-cobalti-oxalate 
occurs in a way fully analogous to that observed in the case of 
the corresponding ferric salt of analogous constitution : in our case, 
carbondiowide is split off, and a pink coloured precipitate of cobalto- 
oxalate: CoC,O, is formed, while a gradually increasing quantity 
of potassium-ovalate goes into solution; this last salt may, for a 
small part, combine with some cobalto-ovalate formed, into a com- 
plex salt of the constitution: A,}Co(C,O,),}, which, however, is 
almost completely dissociated in its components. 
The reaction may principally be formulated in the following way : 
2 {CoC,0,}, K, = 2 CoC,O, + 3 KCO, + 2 CO; 
1) EF. M. Jaraer, Receuil des Trav. des Chim. d. Pays-Bas, 38, 247 —256, (1919); 
idem, Lectures on the Principle of Symmetry and its Applications in All 
Natural Sciences, 2nd Edit., Amsterdam, (1920), p. 216, 249, 250, 317. 
