and Attached Water, 



215 



I have not yet got the cryohydrate of nitrate of calcium. 

 As a cryogen it gives a temperature of —16°. 

 § 156. Separation of Ice $c. from Solutions of Acetate of 

 Sodium, 



Table XXXV. 



NaC 2 H 3 2 per 



cent, by weight. 



H 2 per cent, 

 by weight. 



Temperature 

 at which solidi- 

 fication begins. 



Nature of solid. 



5 



95 



o 



- 2 2 



Ice. 



10 



90 



- 51 





15 



85 



- 91 





20 



80 



-140 





22 



78 



-160 





23-3 



76-7 



-180 



Cryohydrate. 



2(5-6 



73-4 



00 



NaC 2 H 3 2 +?H 2 0. 



The temperature of the cryogen is exactly —18°. For the 

 cryohydrate determination, 7*7032 grms. gave 1*7963 grm. of 

 NaC 2 H 3 2 . For the solubility at 0°, 4-7473 grms. gave 

 1-2646 of XaC 2 H 3 2 . The water-worth is 30. The solid con- 

 stituent was estimated by simple evaporation and heating to 

 incipient fusion. 



§ 157. Separation of Ice fyc. from Solutions of Acetate of 

 Potassium. 



Table XXXYI. 



K C 2 H 3 2 per j H 2 O per cent. J^cS- 

 cent. by weight. by weight. | JSSjJJ 



Nature of solid. 



5 



10 

 15 

 20 

 25 



30 



95 

 90 

 S5 

 80 

 75 

 70 



o 



_ 2 



- 4-6 



- 74 

 -11-2 

 -16 

 -22-5 



Ice. 



The solubility at 0° C. was measured both by directly weigh- 

 ing the dried and fused acetate, and by converting it into a 

 nitrate by frequent treatment with nitric acid and evaporation. 



1. 

 Direct. 

 6*8131 solution gave 

 4-2083 K C 2 H 3 2 , or 

 61-8 per cent. 



Mean . 



2. 



Indirect. 

 7*4837 solution gave 

 4*8573 KN0 3 , or 

 62*8 per cent. K C 2 H 3 2 . 



62*3. 



