Haloid Salts oy Means of Telluric A cid. 



269 



solutions safely dilute. In the experiments of Table II, the 

 expedient was adopted of introducing steam, with the carbon 

 dioxide, so that the volumes might be held constant above the 

 critical concentrations until the volatile halogen had been 

 eliminated as set free. 



Table II. 

 Preliminary Distillations in Steam from Flask. 

 [Initial volume 100 cm 3 : H 2 Te0 4 1 grm.] 



KI 



taken 



KBr 

 taken 



KCl 

 taken 



First 



final 



volume* 



KI 

 found 



Error in 



terms of 



iodine 



Second 



final 

 volumef 



KBr 



found 



Error in 

 terms of 

 bromine 



grm. 



grm. 



grm. 



cm 3 . 



grm. 



grm. 



cm 3 . 



grm. 



grm. 



0-2000 | 0-3000 

 0-2000 0-3000 



0-3 

 0-3 



0-3000 I 0-2000 I 0-3 

 0-3000 0-2000 0-3 



0-5000 

 0-5000 



0-0200 

 0-0200 



0-0200 

 0-0200 



0-0200 ' 00200 I 0-5 

 0-0200 ! 00200 0-5 



63-0 

 55-0 



66-5 

 70-0 



0-5000 

 0-5000 



03 1 



0-3 1 



63-5 1 

 52-0 1 



0-4000 j 

 0-4000 ; 



0-3 j 



03 ; 



525 1 



64-0 i 



1 0-3000 

 | 3000 



0-3 j 

 0-3 | 



64.0 

 63-0 | 



A 











0-1992 



-0-0003 



19-0 



0-3019 



+ 0-0011 1 



0-1996 



| -o-oooi 



185 



0-3001 



+ 0-0001 2 



0-2996 



i o-oooo 



20-0 



1 0-1999 



-0-0001 



0-2993 



| -0-0002 



20-0 



1 0-1998 



-0-0001 



0-4985 



1 -0-0006 



3 19-0 



| 0-4973 



-0-0016 



0-4989 



| -0-0003 



3 17-5 



i 0-4986 



-0-0008 



B 

 0-0206 



j +0-0004 



17-0 



4036 



+ 00021 



0-0200 



| +0-0001 



18-5 



1 0-4036 



+ 0-0021 



0-0201 



+ 0-0001 



17-0 



0-3031 



+ 0-0018 



0-0200 



+ 0-0001 



19-5 



; 03026 i 



+ 0-0015 



62-5 

 66-0 



0-0200 

 0-0200 



+ 0-0001 ! 17-5 0-0240 +0-0028 

 + 0-0001 i 19-5 0-0235 +0-0021 



* H 2 S0 4 of lower concentration. 



1 slow boiling 



2 rapid boiling 



below 30 cm 3 



fH 2 S0 4 of higher concentration. 

 3 [H 2 Te0 4 = 0-2 grm. added.] 



In Table II the results indicate that with the use of steam 

 the iodine may be removed from potassium iodide at volumes 

 ranging between 70 cm3 and 52 cm3 , but there seems to be a 

 tendency toward a very slight deficiency in the iodine (A) 

 except when small amounts (B) of the iodide are used ; while 

 the bromine determinations are high if the boiling is continued 

 after the complete removal of that element, as is the case when 

 the concentration is carried to 17 cm3 after the prolonged boiling. 

 Eapid concentration after a volume of 30 cm3 has been reached 

 tends to lessen the error. 



With the apparatus used in these experiments much difficulty 

 was encountered in regulating the final volumes, which cannot 

 be read with an accuracy of more than 5 cm3 . The exact and 

 final readings of volumes recorded in the table were deter- 

 mined after the experiment by removing the solution to a 



Am. Jour. Sci.— Fourth Series, Vol. XXXVIII, No. 225.— Sept., 1914. 

 19 



