420 ELEMENTARY CHEMICAL MICROSCOPY 



III. Nitric Acid produces an Amorphous or Granular Pre- 

 cipitate. 



Molybdate. 



Silicate. 



Tungstate. 



Titanate. 



Zirconate. 



Note. It must be remembered that the addition of strong 

 nitric acid will cause a crystalline precipitate in the case of many 

 salts of low solubility. 



A somewhat better scheme of separation of the acids has been 

 proposed by C. G. Hinrichs 1 based upon the behavior of their 

 salts toward acetic and sulphuric acids when heated. 



Group I. Salts which when heated with strong acetic acid 

 are decomposed and certain components are volatilized. 



Carbonate (C0 2 ). 



Cyanide (HCN). 



Hypochlorite (to Cl). 



Hyposulphite (SO 2 ). 



Nitrite (oxides of N). 



Sulphide (H 2 S): 



Sulphite (SO 2 ). 



Group II. Salts which when heated with strong sulphuric 

 acid are decomposed and certain components are volatilized. 



Acetate (HC 2 H 3 O 2 ). 



Borate (B(OH) 8 ). 



Bromide (HBr). 



Chlorate (HC1O 8 ). 



Chloride (HC1). 



Cyanate (CO 2 and NH 3 , latter forms (NH^SC^). 



Ferrocyanide (HCN). 



Ferricyanide (HCN). 



Iodide (HI). 



Nitrate (HN0 3 ). 



1 Hinrichs, Microchemical Analysis, p. 116, St. Louis, 1904. 



