4 John White 



lead chlorid if heated with ethyl acetate would yield the same 

 compound, were it not for the fact that the chlorid is soluble in 

 ethyl acetate to so slight an extent as to make it impractical. 



In the endeavor to overcome this objection, a solution of 

 sodium acetate was used instead of the ethyl acetate, with 

 the result that a reaction took place, presumably yielding the 

 above compound, but only as an intermediate product, for 

 the excess of sodium acetate required to bring about a reaction 

 was so large that a further action took place, presumably 

 caused by the halid-acetate first formed uniting with the 

 metallic acetate, yielding a double compound of the general 



type f^ ^r ij Q, -\-M.C^H2,0i, where x may be chlorin, 



bromin, or iodin, and M any metal. 



The above formula has been written as a molecular com- 

 pound, and, so far as the evidence at hand up to the present 

 shows, this seems to be the correct method of expressing 

 it; further evidence is, however, needed before this can be stated 

 with certainty to be the case. 



EXPERIMENTAL 



As previously stated, the iodin salts are the ones described 

 in this paper. These were found to be quite unstable, 

 being easily split up l)y water and many other reagents. This 

 action of M^ater probably furnishes an explanation for the fact 

 that other investigators, notably Tommasi, were unable to 

 isolate the salts, for, unless a very large excess of the metallic 

 acetate be used in the water solution, lead iodid will either 

 not dissolve to any extent, giving instead a basic iodid, or, 

 after going into solution, will be again precipitated out on 

 cooling. Further, in endeavoring to free the salt from the 

 excess of metallic acetate, the water used in washing it would 

 give rise to decomposition products, one of which would 

 always be lead iodid. 



This fact, which was noticed early in the investigation, 

 suggested the necessity of using some other solvent than 

 water. This solvent must, however, be one in which the 



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