Division 4.1.2 Procedure United Kingdom Original text. Later amendments are not shown. 4.1.2.1Identification of mercaptoacetic acid by means of a colour reaction with lead di(acetate) 4.1.2.2Characterization of inorganic sulphides by the formulation of hydrogen sulphide on acidification 4.1.2.3Characterization of sulphites by the formation of sulphur dioxide upon acidification ← Division 4.1.1.2 Division 4.1.2 Division 4.1.2.1 →