1896.] 



HypocJdorites to Chlorates. 



trated sulphuric acid and 2 c.c. hydrochloric acid, required 28*2 c.c. per- 

 manganate, or 00392 gni = l c.c. permanganate. 



Cii) 1'4874 gms. of the double salt in presence of dilute sulphuric 

 acid only required 37-9 c.c. permanganate, or 003924 gm. = I c.c. per- 

 manganate. 



These two numbers are very nearly the same, and in fact agree 

 more than might be expected. Other estimations gave precisely similar 

 results. 



Having thus convinced myself of the applicability of the perman- 

 ganate method in hydrochloric acid solution, a solution of pure potas- 

 sium chlorate containing 0"01 gm. of available oxygen per gram of the 

 solution was made, and the following test experiments performed. 



Two grams of the dried chlorate when ignited left a residue of 1"2176 

 grams of KCl. Therefore oxygen present is 39* 12 % while the calcula- 

 ted quantity is 39*16 °/q. Also 1 c.c. Sn Clg is equal to 635 c.c. perman- 

 ganate, and 1 grm. permanganate is equal to 0*00554 gm. Iron. 



(i) 15*68 gms. SnCl2 + 5055 gms. KClOg required 358 c.c. per- 

 manganate. 



.-. Available oxygen= (15*68 x 6*35-35*8) x 



t 

 = 005047 gm. 



(ii) 16*149 gms. Sn Cl2+5014gms. KC103 = 39*1 c.c. permanganate. 



.*. Available oxygen = 005026 gm. 

 (iii) 3*41 gms. double salt -1-5*047 gms. KClOg^ 24*2 c.c. perman- 

 ganate =242x0 0054 =0*1341 gm. Iron. 



.-. 5*047 gms. KClO3 = 005043 gms. oxygen, 

 (iv) 3*12 gms. double salt-f 5*039 gms. KC103=17 c.c. perman- 

 ganate. 



.-. 5*039 gms. KClOg = 0*05036 oxygen. 



•00554 



Method of experiment. Sn Clg method. 



1 



Ferrous Ammonio- 

 Sulphate method. 



No. of experiment 



I II 



Ill 



IV 



Estimated value 

 Calculated value 



0*05047 

 0-05055 



005026 

 005014 



005043 

 0-05047 



005036 

 0-05039 



(iii) The solution of the chlorate was distilled with pure concen- 

 trated hydrochloric acid in Bunsen's distilling bulb. Various other 

 acids (boric acid, phosphoric acid, acetic acid, sulphuric acid) were tried. 

 The first three failed to decompose the chlorate. As calcite was used 

 to carry off the chlorine, &c., from the bulb to the absorption apparatus, 



