Magnesium Sulfate

Dried Magnesium Sulphate BP Magnesium Sulfate Dried Epsom Salts Magnesium Sulphate Dried is offered in BP grade Preparation Magnesium Sulphate Paste DEFINITION Dried Magnesium Sulphate contains not less than 62.0% and not more than 70.0% of MgSO4. It may be prepared by drying magnesium sulphate at 100° until it has lost approximately 25% of its weight. CHARACTERISTICS A white powder. Freely soluble in water; dissolves more rapidly in hot water. IDENTIFICATION Yields the reactions characteristic of magnesium salts and of sulphates. TESTS Acidity or alkalinity To 10 ml of a 7.5% w/v solution in carbon dioxide-free water add 0.05 ml of phenol red solution. Not more than 0.2 ml of either 0.01M hydrochloric acid VS or 0.01M sodium hydroxide VS is required to change the colour of the solution. Arsenic 0.33 g dissolved in 25 ml of water complies with the limit test for arsenic, (3 ppm). Heavy metals Dissolve 1.3 g in 20 ml of water and add 1 g of ammonium chloride. 12 ml of the resulting solution complies with limit test A for heavy metals, Appendix VII. Use lead standard solution(1 ppm Pb) to prepare the standard (15 ppm). Iron 0.33 g dissolved in 10 ml of water complies with the limit test for iron, Appendix VII (30 ppm). Chloride 0.13 g dissolved in 15 ml of water complies with the limit test for chlorides, Appendix VII (400 ppm). Insoluble matter 7.5 g dissolves in 20 ml of water, producing a solution which may be slightly turbid at first but which becomes clear in a few minutes