522 Mr. A. H. Church on some Reactions of 



performance and expenditure, and in searching for the condi- 

 tions of that equivalence ? 



To enter further upon this subject would lead us beyond the 

 intended scope of this publication ; and I therefore close in the 

 hope that the reader will please to supplement by his own reflec- 

 tion much that in this tract has been left unsaid. 



LXVIII. On some Reactions of Hydride ofBenzoyle. 

 By Arthur H. Church, B.A. Oxon.* 



Action of Sodium on Hydride of Benzoyle. 



IT has been observed that when sodium is heated with pure 

 hydride of benzoyle, although the metal disappears, there is 

 no evolution of hydrogen. While recording this phenomenon in 

 his Traite de Chimie Organique, Gerhardt, struck by its singu- 

 larity, expressed a doubt as to the accuracy of the observation. 

 The point evidently required further elucidation, yet the prone- 

 ness of the materials to oxidize and otherwise change rendered 

 the investigation by no means inviting. However^ in pursuing 

 it, I have been rewarded with several interesting results which I 

 would now briefly record. 



Having prepared some hydride of benzoyle in a state of perfect 

 purity, I determined to bring it into contact with* sodium in the 

 presence of a liquid solvent itself inert. For this purpose I chose 

 that portion of coal-naphtha which boils between 100° and 

 110° C. After having rendered it anhydrous, I dissolved in it a 

 weighed quantity of the hydride (about . one-twentieth of the 

 naphtha used). Into the solution, contained in a small long- 

 necked flask with a condensing tube, a clean weighed globule of 

 sodium attached to a platinum wire is introduced, and the flask 

 then gently warmed until an action has been set up. Occasion- 

 ally it becomes necessary to moderate the violence of the change 

 by cooling the vessel. No gas whatever is evolved ; and when 

 the reaction is complete, the globule of fused sodium remains 

 bright even when the liquid is long kept boiling, the dark green 

 crusts of the new sodium-compounds ceasing to be formed. But 

 further experiments showed that this reaction is more completely 

 under control when sodium-amalgam is used in place of the 

 pure metal : the new body is then obtained in nearly colourless 

 gelatinous flakes. In order to determine quantitatively the 

 nature of the change, I have weighed in several experiments 

 the residual sodium withdrawn from the flask when cold, and 

 plunged in a counterpoised vessel of Persian naphtha — the 



* Communicated by the Author. 



