QUESTIONS AND ANSWERS 37 



PHENOLS 



Give the composition and the properties of phenol. 



Pure phenol, CoHbOH, occurs in colorlesis crystals which are 

 deliquescent and soluble in fixed oils, glycerine and water. It has 

 a characteristic, aromatic odor ; when diluted, it has a sweetish and 

 afterward burning; caustic taste and produces a benumbing and 

 caustic effect and even blisters on the sMn. It is strongly poisonous 

 and a powerful disinfectant. 



What is phenol? For what is it used and from what is it obtained? 



See answer to preceding question. 



Phenol is used in surgery for its germicidal, antiseptic and slight 

 anaesthetic effects. Used as a disinfectant and deodorant in cess- 

 pools, stables, etc. It is obtained by fractional distillation of crude 

 carbolic acid which is obtained during the distillation of coal-tar. 



What is salol? Give its properties and uses. 



Salol, a compound of salicylic acid and phenol, is a white, crystal- 

 line, almost tasteless powder, with a faintly aromatic odor; nearly 

 insoluble in water, but readily soluble in alcohol and ether. It is 

 made by the action of suitable dehydrating agents upon a mixture 

 of phenol and salicylic acid. It is used as an antirheumatic, anti- 

 pyretic and intestinal antiseptic. 



PETEOLEUM 



What is petroleum? Name the important derivatives of petroleum 

 used in medicine. 



Petroleum is a product of the decomposition of organic matter, 

 mostly of the fats and oils of fish and other aquatic animals. It is 

 a mixture of the various liquid and solid paraffins, often cont ainin g 

 in solution the gaseous and solid members of this group and ialso 

 small quantities of coloring and other matters. 



Derivatives used in medicine: petrolatum (cosmoline, vaseUne) 

 and liquid petrolatum. 



Mention the source and important properties of vaseline. 



Vaseline is obtained from petroleum by distilling off the lighter 

 and more volatile portion and purifying the residue. It is a fat- 

 like mass, varying in color from yellowish-white to light amber, 

 slightly fluorescent, odorless and tasteless; when heated it gives 



