Technical Methods of Ore Analysis
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from ... Show synopsis This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ...also 2.5 grams of ammonium nitrate in 100 cc. 241. Dry the filter and precipitate and ignite them in a weighed platinum crucible, first at a very low temperature so as to carbonize the filter without decomposing the precipitate. Now break up the residue with a platinum rod and then heat at a gradually increasing temperature to the full power of a Bunsen burner and continue the ignition until the residue is perfectly white. Cool and weigh. Now fill the crucible half full of hot water, add from 5 to 20 drops of strong hydrochloric acid and heat until the precipitate has dissolved. Filter off on another small ashless filter any silica or ferric oxide that may remain, ignite and weigh. The difference between the two weights is the weight of the Mg2P2O7, which, multiplied by 0.27837, will give the weight of the phosphorus. Magnesia mixture.--Dissolve 11o grams of crystallized magnesium chloride (MgCl2+6HjO) in water and filter. Dissolve 280 grams of ammonium chloride in water, add a little bromine water, and a slight excess of ammonia, and filter. Add this solution to the solution of magnesium chloride, add enough ammonia to impart a decided odor, dilute to about 2 liters, shake vigorously from time to time, allow to stand for several days, and filter into a small bottle as required for use. Ten cc. of this solution will precipitate about 0.15 gram of P2O, i. Blair, Chem. Anal, of Iron. CHAPTER XXIII. POTASSIUM AND SODIUM. Almost the only occasions when the technical metallurgical chemist has to make quantitative determinations of potassium and sodium are in the analyses of silicates, such as clays, etc. Descriptions of methods will, therefore, be confined to such as apply to these substances. 242. Method of J. Lawrence Smith.--Principle.--The substance is heated..