Identification Tests Sulfate

Testing of phthalocyanines includes crystallization (qv), flocculation, and appHcation in paints, plastics (qv), and printing inks (1). The ASTM standard specifications include CuPc in dry powder form for various appHcations (153). The specifications cover color (qv), character or tint, oil absorption, reactions in identification tests, and dispersions and storage stabiUty. Quantitative deterrninations are possible with ceric sulfate (30) or sodium vanadate (154). Identification methods are given (155), including tests for different appHcations. 

A. While stirring to produce a uniform dispersion, add about 1 g of powdered sample to 50 mL of warm water. Continue stirring until a colloidal solution is produced, and then cool to room temperature. Save part of this solution for Identification Test B. Add 10 mL of cupric sulfate TS to about 10 mL of the solution. A fluffy, blue-white precipitate forms. 

Aluminum Identification Test, 753 Aluminum Magnesium Silicate, 41 Aluminum Potassium Sulfate, 21 Aluminum Sodium Sulfate, 21 Aluminum Sulfate, 22 Ambrette Seed Liquid, 23 Ambrette Seed Oil, 23, 596 Aminoacetic Acid, 186 A-[4-[[(2-Amino-l,4-dihydro-4-oxo-6-pteridinyl)methyl] amino] benzoyl] -l-glutamic Acid, 157 3 - Amino-7-dimethylamino-2-methylphenazine Chloride, 861 L-2-Aminoglutaramic Acid, 175 L-2-Amino-5-guanidinovaleric Acid, 32, (S3)5... 

Chloride and Sulfate Limit Tests, 757 Chloride Identification Test, 753 Chlorinated Compounds, 817 Chlorine, 99... 

The following identification tests are mentioned in the USP XXI (3) under hyoscyamine sulfate. 

Since zinc, aluminium and lead(II) hydroxides are white, additional tests are needed to distinguish between them. A quick identification test for lead(II) ions depends upon the fact that lead(II) sulfate is insoluble in water, whereas aluminium and zinc sulfates are soluble. Addition of dilute sulfuric acid to lead(II) ions will therefore precipitate the lead(II) sulfate ... 

As also the oxides of phosphor, they form polymers willingly. Sulfuric acid is a strong acid, a dehydrating agent and an oxidizing agent. Most inorganic salts of the anion sulfate are water soluble. One exception is barium sulfate and the characteristic of this salt is used in the test. The identification test for sulfates is special since the purposes of the different steps of the analysis are explained in parentheses in the pharmacopoeial text. 

The sulfate content is estimated by precipitating the sulfate present in the substance to be examined with barium, and comparing the resulting opalescence to the opalescence obtained in a standanl of known sulfate content. It is the same chemistry used in the pharmacopoeia identification test of sulfates. 

Among the anions, only silicofluorides interfere they react similarly to sulfates. The test solution must necessarily be neutral. When alkaline solutions are present, as when testing a sodium carbonate extract, it is advisable to acidify a few drops of the test solution with hydrochloric acid, evaporate to dr5mess on the water-bath, and then to add barium carbonate. After this treatment, the limit of identification is about double that with neutral solutions. 

Identification A 1 20 aqueous solution gives positive tests for Aluminum, for Ammonium, and for Sulfate, Appendix IIIA. Assay Not less than 99.5% and not more than 100.5% of A1NH4(S 04)2 12H20. 

Identification A 1 10 aqueous solution gives positive tests for Aluminum and for Sulfate, Appendix IIIA. 

Identification A sample gives positive tests for Ferrous Salts (Iron) and for Sulfate, Appendix IHA. 

Identification Transfer 1 mL of the Sample Solution remaining at the end of the test for Total Lactic Acid (below) into a 25-mL glass-stoppered test tube, add 0.1 mL of cupric sulfate solution (1 g of CuS04-5H20 in 25 mL of water) and 6 mL of sulfuric acid, and mix. Stopper loosely, heat in a boiling water bath for 5 min, and then cool in an ice bath for 5... 

Identification A 1 10 aqueous solution gives positive tests for Sodium, Appendix IIIA. After acidifying with hydrochloric acid and boiling gently for 20 min, it responds to the tests for Sulfate, Appendix IIIA. 

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