HYDRURET OF BENZOYL. 853 



with an alcoholic solution of potash, it passes in a few seconds 

 into benzoate of potash which floats upon the alcohol ; a portion of 

 the hydruret of benzoyl which loses oxygen being converted at 

 the same time into an oil of unknown composition retained in 

 solution by the alcohol. 



Chloride of benzoyl C 14 H 5 O 2 + Cl=Bz,Cl ; is formed on 

 transmitting chlorine gas through dry hydruret of benzoyl, so 

 long as hydrochloric acid is disengaged, and heating the yellow 

 liquid to expel the excess of chlorine, till it becomes colourless. 

 The atom of hydrogen of the hydruret of benzoyl is removed 

 by one atom of chlorine, and replaced by another, as in ordi- 

 nary substitutions. 



Chloride of benzoyl is a colourless liquid, of a very penetrat- 

 ing and disagreeable odour, which affects the eyes ; its density 

 is 1,106'; it boils at 383 (195 centig.). It may be distilled from 

 lime or barytes without change. It mixes with ether and 

 bisulphuret of carbon without decomposition. Cold water 

 converts it more slowly than hot water into hydrochloric and 

 benzoic acids ; with alkalies it produces an alkaline benzoate 

 and chloride of the same metal. With alcohol it produces 

 benzoate of ether and hydrochloric acid. 



Bromide and iodide of benzoyl crystallize in transparent 

 colourless plates. 



Sulphuret of benzoyl is obtained by distilling chloride of ben- 

 zoyl with sulphuret of lead, as a yellow oil, which fixes as a soft 

 crystalline mass, having a peculiar disagreeable odour. 



Cyanide of benzoyl is prepared by distilling chloride of ben- 

 zoyl with cyanide of potassium ; it is, after rectification, a 

 colourless oil having a strong cinnamon odour which excite& 

 tears, 



Benzamide, Bz + NH 2 =Bz,Ad ; is prepared by saturating 

 chloride of benzoyl by dry ammoniacal gas ; pulverising the 

 white solid mass which is formed, washing it with cold water to 

 remove sal ammoniac, and dissolving the residue in boiling 

 water, which deposits the benzamide on cooling. It crystallizes 

 in right rhomboidal prisms, or in small tables of a pearly lustre, 

 fuses at 239 into a colourless liquid, and may be distilled at a 

 higher temperature. It is soluble in alcohol and ether, as well 

 as in water. Acids and alkalies decompose it, with the pre- 

 sence of water, into ammonia and benzoic acid. 



