PREPARATION OF SOLUTIONS FOR ANALYSIS OF SORGHUIM, ETC. 503 



PREPARATION OF SOLUTIONS FOR ANALYSIS OF SORGHUM, MAIZE, AND 

 SUGAR-CANE JUICES. 



Fehling's Solutmi. 



Weigh out the following: C^H^K Na06.4H20 crystallized Ro- 

 chelle salt, 2595 grams ; powder it aud put it iu a large glass balloon 

 flask, holding at least 20 liters; add NaHO caustic soda, 820.8 grams, 

 and then pour over it 7 liters of water, and shake up until dissolved. 



Dissolve in 3 liters of water 519.6 grams CuSO^.SHaO crystallized 

 sulphate of copper, and add the solution of the copper salt to the so- 

 lution of Rochelle salts and caustic soda ; then add water enough to 

 make 15 liters iu all. 



It is well to powder the Rochelle salts and the sulphate of copper, 

 to hasten the solution of them. It is of advantage to place the hy- 

 drate of soda upon the powdered Rochelle salts, in order that its solu- 

 tion may be readily effected, without allowing it to come in contact 

 directly with the glass. 



Permanganate Solution. 



131.748 grams (132.) of crystallized permanganate of potash, 

 KgMugOg, dissolved iu 30 liters of water, gives a solution of the 

 proper strength. 



100 c. c. of decinormal oxalic acid solution should equal 72 c. c. of this 

 permanganate solution. 



Basic Acetate of Lead Solution. 

 4500 grams of pulverized lead acetate, Pb (€211302)2, are mixed 

 ■with 2700 grams of lead oxide, PbO, and 2500 c. c. of Avater added to 

 the mixture. It is then boiled for two hours in an iron pot, with stir- 

 ring, the evaporated water being replaced. Filter in bottles. 



Ferric Alum Solution. 

 Ferric alum, 500 grams; water, HgO, 5 liters; sulphuric acid, 

 H2SO4, 250 c. c. Dissolve the powdered alum in the water, and then 

 add the sulphuric acid. 



