certain Tartrate Solutions. 



2ri5 



The values for the specific rotation are slightly higher than 

 found by Landolt for similar solutions. 



Having established the value of the specific rotation, for the 

 salt employed, I next sought to determine the variations in 

 this when various inactive substances were dissolved with 

 definite amounts of the potassium antimony tartrate. All 

 attempts to prepare solutions with iodides, even in small 

 amount, failed because of more or less rapid precipitation of 

 oxyiodide. This did not take place with pure chlorides or 

 bromides. I likewise found it difficult to prepare stable solu- 

 tions with any potassium salt. Even potassium chloride and 

 nitrate gave crystalline precipitates on standing but a short time, 

 except when added in very small amount. Much better results 

 were obtained with sodium and ammonium salts. The data 

 obtained can be best shown in tabular form, and hence they 

 will be presented in that way. The first column in the table 

 below shows the amount of inactive salt dissolved with 5 gril 

 of the tartrate in 100 oc at 20° C. The second column gives the 

 observed rotation for the tube 400 mm in length. The third 

 column gives the specific rotation calculated by the formula 



[cc] = ^, and corrected for the error of the flask. In the 



fourth column is given the change from the normal specific 

 rotation of the active salt, and in the last column it is shown 

 in several cases how this varies by increase in the amount of 

 the inactive salt. 



Formula and amount 

 of inactive salt. 



Observed 

 rotatiou 



Specific 



rotation 



[a] 



Deviation Change 

 from in this, 



normal. 



NaCl 

 NaCl 

 NaCl 



NH 4 C1 

 NH 4 Ci 



NaN0 3 



NaN0 3 

 NaN0 3 



NH 4 X0 3 

 NH 4 N'0 3 

 NH 4 N0 3 



ogm. 

 10 



15 



5 



10 



5 

 10 

 15 



5 

 10 

 15 



NaC 2 H 3 2 .3H 2 5 

 NaC 2 H 3 2 .3H 2 10 



KC1 2 



KN0 3 2 



KBr 5 



28-075 

 27-138 

 27-460 



28-188 

 27-965 



28025 

 27-718 

 27-427 



28155 

 27-865 

 27-620 



25-745 

 24-676 



28-200 

 58-205 

 27-945 



140-613 

 138-925 

 137-532 



141-179 

 140-053 



140-363 

 138-825 

 137-367 



141013 

 139-561 

 138-334 



128-944 

 123-589 



141-238 

 141-264 

 139-953 



- 2 



- 3 



— 1 



— 1 



- 2 



660 



348 

 74L 



094 

 220 



910 

 448 

 906 



260 



712 

 939 



12-329 



17-684 



•035 

 ■009 



1-320 



1-688 

 1-393 



1-126 



1-538 

 1-458 



1-452 

 1-227 



5-355 



The last three solutions were clear when used, but on 

 standing a few hours a crystalline precipitate separated out. 



