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 CI). 



Hyposulphite (S0 2 ). 



Nitrite (oxides of N). 



Sulphide (H 2 S). 



Sulphite (SO2). 

 Group II. - - Salts which when heated with strong sulphuric 

 acid are decomposed and certain components are volatilized. 



Acetate (HC 2 H 3 2 ). 



Borate (B(OH) 3 ). 



Bromide (HBr). 



Chlorate (HC10 3 ). 



Chloride (HC1). 



Cyanate (C0 2 and NH 3 , latter forms (NH 4 ) 2 S0 4 ). 



Ferrocyanide (HCN). 



Ferricyanide (HCN). 



Iodide (HI). 



Nitrate (HN0 3 ). 



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



