[ARCHIBALD 4 m' intosh] VALENCY OF ELEMENTS 43 



Keeping in mind the work of Friedel, we tried to produce addi- 

 tion compounds of the . acids and organic bodies. Of these we in- 

 vestigated but three classes, the ketones, the alcohols, and the ethers, 

 and succeeded in isolating the compounds ^ and in analysing them. 

 They are colourless, crystalline bodies with melting points, in general 

 well above the melting points of the substances from which they 

 are formed. They easily form supersaturated solutions, from which 

 they can be crystallised by a small amount of the solid phase. 



In the case of the compound formed from hydrogen iodide and 

 ether, the analyses showed one molecule of acid to one of ether. Assum- 

 ing the oxygen tetravalent, the constitution of the body can ])e repre- 

 sented thus: — 



C.H,„0 <^ or C,H,„0 = IH ; 



and since iodine in hydriodic acid at low temperatures is a monad,^ it 

 seems probable that the former structure is the correct one. 



In the following table we give a summary of the results obtained 

 from a study of these addition compounds. In the majority of cases 

 the proportion of acid to base was obtained by analysis; in three cases 

 by synthesis in a manner previously described. The decomposition 

 (melting) point of the compound is also given and the quantivalence 

 of the oxygen,^ assuming that the aoid molecules attach themselves ta it. 



» Proc. Chem. Soc., June, 1904. 



* Proc. Roy. Soc, May, 1M4. 



• The oxygen valency is probably r.ot greater than six; the chlorine may 

 increase to three. 



