2G8 Mr. Brown on the Products of the Soda Manufar/ 



3. Chloride of sodium. 



The soda ball was digested with nitric acid and filtered, and from the 

 filtered solution the chlorine was precipitated by nitrate of silver : — 



Sodar>all. AgCl. CI. NaCl. Na CI p.c. 



98 gave, 5*400 1*350 2-250 2-295 



100 — 3-679 0912 1532 1532 



Average, 11.39 



4. Soda. 



The total quantity of available soda, that is, soda existing as carbonate, 

 sulphuret, and hydrate, was determined in the following manner: — A por- 

 tion of the soda ball was thrown on a filter and washed with warm water, 

 until all the soluble matter was taken up ; the filtered solution was then 

 exactly neutralised by dilute sulphuric acid, which was afterwards precipi- 

 tated by chloride of barium. From the quantity of sulphate of bary tes thus 

 obtained, the amount formerly got from the sulphate of soda was deducted, 

 and from the remainder the per centage of alkali was calculated : — 



Soda Ball. BaOS0 3 BaOS0 3 BaOS0 3 p.c. Soda p.c. 



44-60 gave, 4060 91-031 — 1-872 = 89-159 24593 



100 — 88-96 88-960 — 1-872 = 87*088 24-024 



48-50 — 42-76 88-164 — 1-872 = 86-292 23-800 



Average, 24-138 



5. Sulphur. 



The amount of sulphur was determined in two different ways : — 1st, The 

 soda ball, after being very carefully pulverised, was intimately mixed with 

 about four times its weight of nitrate of potash, and heated in a covered 

 platinum crucible. The nitrate of potash was thus decomposed, and the 

 sulphur converted into sulphuric acid by the oxygen of the nitric acid : — 



KO NOA + S = S0 3 + KO + N0 2 



The fused mass was dissolved by muriatic acid, and after filtering the 

 solution, the sulphuric acid was precipitated by chloride of barium. 

 2d, The soda ball, moistened with a small quantity of water, was inti- 

 mately mixed with a quantity of finely pulverised chlorate of potash, and 

 to this muriatic acid was added, drop by drop, until, upon a fresh addition 

 of acid, no more gas was evolved. The flask containing the substance 

 was then gently heated by means of a water bath, care being taken to 

 keep the temperature below 180° F., as chlorous acid explodes with 

 great violence at about 200° F. When all action had ceased, the solution 

 was filtered, and the sulphuric acid precipitated by chloride of barium. 

 From the weight of the sulphate of barytes thus obtained, the former 

 quantity, 1*872, was deducted, and from the number thus found, the 

 amount of sulphur was calculated : — 



