for the Determination of the AlkoM Metals. 383 



were redissolved in a little water and then subjected to one or 

 two similar treatments with perchloric acid. The residues 

 were digested with the alcoholic washing liquid (1)7 per cent 

 alcohol, containing about 0*1 per cent of perchloric acid), trans- 

 ferred to an asbestos filter in the perforated crucible, washed, 

 dried at about 130°, and weighed. In some cases the precip- 

 itate was redissolved and again treated after decantation of the 

 solution before repeating the treatment with perchloric acid 

 and transferring the precipitate to the filter. These details of 

 treatment are indicated. 



Table II. 

 The Determination of Potassium as the Perchlorate. 



KCl 

 taken 

 grm. 



NaCl KCIO4 

 taken found 

 grm. grm. 



Theory Error HCIO4 



for grm. 70% 

 KCIO4 cm=^ 

 grm. 



Filtrate 



(Approx.) 



cm3 



A 



The transfer made with the washing solution. 



* 0-1007 



* 0-1009 

 *0-10U 



* 0-1005 



01862 0-1871 —0-0009 



0-1870 0-1875 —0-0005 



0-1876 0-1884 -0-0008 



0-1862 0-1867 -0-0005 



0-1 



60 



0-1 



60 



0-1 



60 



0-1 



60 



B 



The transfer effected with the use of the filtrate. 



t 0-1000 







0-1866 



0-1858 



+ 0-0008 



3X0-1 



20 + 5 



t 0-1020 



.... 



0-1894 



0-1895 



+ 0-0001 



3X0-1 



20 + 5 



X 0-1005 



0-1 



0-1872 



0-1868 



+ 0-0004 



0-1 



20 + 5 



§ 0-1033 



0-1 



0-1924 



0-1920 



+ 0-0004 



0-1 



20 + 5 



§ 0-1016 



0-1 



0-1894 



0-1889 



+ 0-0005 



0-1 



20 + 5 



1 0-3015 



0-1 



0-5622 



0-5602 



+ 0-0020 



3X0-1 



20 + 5 



1 0-3012 



0-1 



0-5622 



0-5596 



+ 0-0026 



3X01 



20 + 5 



tO-3021 



0-1 



0-5615 



0-5613 



+ 0-0002 



3X0-1 



10 + 10 + 5 



^0-3002 



0.1 



0-5571 



05578 



— 0-0007 



3X0-1 



10 + 10 + 5 



10-3013 



0-5 



0-5613 



0-5598 



+ 0-0015 



3X0-1 



lOf 10 + 5 



tO-3008 



0-5 



0-5603 



0-5589 



+ 0-0014 



3X0-1 



10 + 10 + 5 



* One evaporation in glass. 



f Three treatments and evaporations in glass, following solution in each 

 case in the least amount of water. 



X One treatment in platinum. 



§ One treatment in quartz. 



II Three treatments and evaporations in platinum without decantation, 

 following solution in each case in the least amount of water. 



^ Three treatments and evaporations in platinum; digestion of the residue 

 with 10 cm^ of w^ashing solution, decaiitation, solution, evaporation, digestion 

 and transfer with 10 cm^ of washing liquid. 



