/. Remsen — Phosphorus Oxychloride. 



CI 

 According to this, phosphorus is trivalent in the oxychloride, 

 the same as in the trichloride. The grounds for this assump- 

 tion are as follows : 



1. The oxychloride can be converted into the form of vapor 

 without undergoing decomposition, which shows that it cannot 

 belong to the class of compounds known as molecular compounds, 

 inasmuch as these latter are decomposed into simpler molecules 

 by the action of heat. But, if it is not a molecular compound 

 its structure must be similar to that of phosphorus trichloride, 

 which is the type of the atomic compounds of phosphorus. 



2. Thorpe* has recently shown that the specific volume of 

 oxygen in phosphorus oxychloride is 7*89 and that of sulphur 

 in the thiochloride 2266. These values agree closely with those 



From this the conclusi 



ride and thiosulphide 



phosphorus by only one affinity each, and hence that the struc 



tures of these bodies are represented by the formulas : 

 CI CI 



P-O-Cl and P-S-Cl. 



It may be remarked in regard to the former of these grounds 

 that Wiirtzf has shown that phosphorus perchloride itself, the 

 most decided representative of molecular compounds, may, un- 

 der proper conditions, be converted into the form of vapor with- 

 out undergoing decomposition, and hence there is no good reason 

 for assuming that the perchloride differs from ordinary chemical 

 compounds in any essential particular. If, however, the perchlo- 

 ride is a true chemical compound, an atomic in contradistinction 

 from a molecular compound, then phosphorus is in it quinquiva- 

 leni, while it is certainly trivalent in the trichloride. If, further, 

 we once grant that phosphorus can and does act as a quinquiva- 

 lent element, we would naturally suppose it to act so in the 

 oxychloride, and hence to the latter would be given the formula, 



* Berliner Berichte, viii, 3 



