476 J. M. Ordway — Waterglass. 



In preparing silicic acid hydrate by mixing weak solutions 

 of sodium waterglass and ammonium chloride, it was found 

 advantageous to add some methyl alcohol to aid in the disinte- 

 gration of the coagulum. The precipitate was hard pressed, 

 crushed and washed with water and alcohol. After a second 

 washing the pressed cake was dried in the air. The hydrate 

 seems to have no fixed and definite composition, but after 

 becoming apparently dry it may continue to part with water, 

 like an efflorescing salt. Thus when some which appeared at 

 first to be a sexhydrate was kept in dry air three weeks it was 

 reduced to 2Si0 2 + H 2 0. 



Lithium sulphate being decomposed by barium hydroxide 

 the very dilute solution was boiled down in a nickel dish till it 

 let fall some of the oxide. This saturated solution contained 

 about seven per cent of LiH/O. When it was digested, at the 

 ordinary temperature of the air, with enough of the silica to 

 form a monosilicate, very nearly all of the silica was taken up 

 and the filtered solution showed 8\5 p. c. of Li 2 Si0 3 besides a 

 slight excess of LiHO. 



9b. 128 g. of this clear liquid, in a glass dish which would allow 

 the slightest change to be seen, were confined over calcium chlor- 

 ide, the temperature at no time exceeding 22° C. In five days a 

 faint deposit began to appear and the loss amounted to 32 g. 

 The point of saturation being thus reached, it appears that lith- 

 ium monosilicate is perfectly soluble in water and the solution 

 may contain as much as eleven per cent of Li 2 Si0 3 . 



10. 30 cc of dilute chlorhydric acid (3-65 g. of HC1 in 100 cc ) 

 mixed with 50 g. of a 5 p. c. solution of Li 2 Si0 3 caused no appa- 

 rent change. The addition of 40 oc of alcohol produced a 

 soluble cake weighing 4*7 g. and containing 35 p. c. of Li„0 , 2Si0 3 . 



11. 304 g. of a solution containing 6 p. c. of Li 2 Si0 3 and 0*3 

 p. c. of Li„0 treated with 149 g. of dilute nitric acid (5*4 p. c. 

 N 2 5 ) gave with 370 ce of methyl alcohol 36 g. of cake mostly 

 soluble in less than three parts of water. It showed 36*5 p. c. of 

 10Li„O , 23SiO 2 . The residue consisted chiefly of 05 g. of Si0 2 . 



Some of the cake solution being evaporated began to show 

 a deposit when it contained 24 p. c. of the silicate. The evap- 

 oration being continued till the percentage amounted to 30 it 

 became a very stiff, opaque, amorphous mass. This dissolved 

 completely in its own weight of water. This latter solution 

 with half its bulk of alcohol gave a deposit holding 39 p. c. of 

 10Li 2 O27Si0 2 and soluble in twice its weight of water. 



12. 105 g. of a solution containing 7 p. c. of Li 2 SiO a and 0-2 

 p. c. of Li n O with 43 g. of dilute nitric acid (10 p. c. N 2 6 ) and 

 50 g. of 18 p. c. LiCl yielded 9 g. of cake not entirely soluble. 

 The soluble part amounted to 21 p. c. of 10Li 2 O-19SiO 2 . 



The mother liquor with 100 cc of methyl alcohol gave 7*9 g. 



