96 

 27 



METHODS OF ANALYSIS 



Table l.— Munson and Walker's Table.- 



[Expressed in milligrams.) 



[Chap. 



-Continued. 



28 



II. A. H. Low Volumetric Method, Modified.^ — Tentative. 



Standard thiosulphate solution. — Prepare a solution of sodium thiosulphate 

 containing 19 grams of pure crystals in 1 liter. Weigh accurately about 0.2 

 gram of pure copper foil and place in a flask of 250 cc. capacity. Dissolve by warming 

 with 5 cc. of a mixture of equal volumes of strong nitric acid and water. Dilute 

 to 50 cc, boil to expel the red fumes, add 5 cc. of strong bromin water, and boil 



