Zinc Oxide

Zinc Oxide-BP

 

 

Determination
Specification
   
Characteristics A soft, White or faintly yellowish white amorphous powder, free from grittiness, odorless practically insoluble in water and in ethanol (96 %)it dissolve in dilute mineral acids.
Identification A. Becomes yellow when strongly heated. The yellow Color disappears on cooling.
B. Dissolve 0.1 g in 1.5 ml of 2 M hydrochloric acid And dilute to 5 ml with water.The solution yields theReaction characteristic of zinc salts.
Alkalinity Shake 1.0 g with 10 ml of boiling water; add 0.1 ml of phenolphthalein solution and filter. If the filtrate is red not more than 0.3 ml of 0.1 M hydrochloric acid is Require to discharge the color.
Carbonate & Sub-
stances Insoluble
in acids.

Dissolve 1.0 gm in 15 ml of 2M hydrochloric acid. No.
Effervescence is produced and the solution is not More opalescent than reference suspension II Appendix IV A, and is colorless,appendix B,Method II

Arsenic 0.2 g complies with the limit test for arsenic Appendix VII (5 ppm)
Cadmium Not more than 10 ppm of Cd when determined by atomic absorption spectrophotometry, Appendix IID, Method II, measuring at 228.8 nm and using either an air –acetylene or an air propane flame.dessolve 2 g of the substance being examined in 14 ml a mixture of equal volumes of water and –cadmium and lead –free nitric acid, boil for 1 minute, cool and dilute to 100 ml with water Use cadmium solution Asp, suitably diluted with a 3.5% v/v solution of cadmium- and lead free nitric acid, to prepare the standard solutions.
Iron Dissolve 50 mg in 1 ml of 2-M hydrochloric acid and dilute to 10 ml with water. The resulting solution complies with the limit test for iron, Appendix VII (200 ppm). Use 0.5 ml of mercaptoacetic acid in the test.
Lead Not more than 50 PPM of Pb when determined by method II For atomic absorption spectrophotometry Appendix II D, Measuring at 283.3 nm or 217.0 nm using air- acetylene flames. Dissolve 5 g of the substance being examined in 24 ml of a mixture of equal volumes of water and cadmium –and lead –free nitric acid, boil for 1 minute, cool and dilute to 100 ml with water. Use lead solution Asp Suitably diluted with a 3.5 % v/v solution of cadmium – and lead free nitric acid, to prepare the standard solutions.
Loss On Ignition When ignited at 500 Deg.C, loses not more than 1.0 % of its weight.Use 1 g.
Assay Carry out the complexometric titration of zinc Appendix VIII D, using a solution of 0.15 g in 10 ml of 2 M acetic acid. Each ml of 0.1-M disodium edetate VS is equivalent to 8.14 mg of ZnO. Zinc Oxide contents not less than 99.0 % and not more than 100.5 %)