tes 
retical and the experimental line is not possible. Qualitatively the 
agreement is perfect. It appears from the course of the lines 1 and 
2 in fig. 2 that the middle of the horizontal part of these lines lies 
at a concentration equal to } 4. Hence at ci, = 10> 8 for Agl, which 
corresponds with a potential of + 0.54 Volt. It appears from Rrepy’s 
line that the middle of the horizontal portion really lies at this potential. 
This is different with a line given by Rewpy for AgBrO, in 0.5 
molecular KBrO,. Here the middle of the horizontal portion lies at 
about 0.470 V, corresponding with a silver ion concentration of 
105. Then the product of solubility of AgBrO, would be 10-22. 
This value is much too small for AgBrO,. For the solubility BOrreEr *) 
found 7 >< 10 mol. per L. As for this dilution AgBrO, is almost 
totally ionized, the product of solubility will be about 5 > 10%. 
The product of solubility found from Rrrpy’s line, is therefore cer- 
tainly not that of AgBrO,. Its value agrees pretty well with that 
of AgBr, which leads us to the supposition that Ruxpy’s line does 
not refer to AgbrO,in KBrO,, but to AgBr in KBr, which might be 
the case if the bromate used was contaminated with bromide. This 
supposition is supported by what follows. For the potential of 
AgBrO, in 0.5 molecular KBrO, without polarisation Reepy finds 
0.400 V., which yields a product of solubility for AgBrO, of 10-7. 
As was demonstrated above this value is too low. If we assume the 
measnred potential to refer to AgBr in Kbr, the solution used would 
have to contain 10—- KBr, for which it would be therefore neces- 
sary that the bromate used was contaminated with 0.002°/, bromide. 
Besides, the length of the horizontal piece in the line of Rerpy 
is slightly more than 0.1 Volt, as is required for a silver salt, for 
which 1/4=10-° in a solution which is 10— > molecular at the 
anion. For AgBrO, in 0.5 molecular KBrO, the horizontal portion 
would. have to be about twice as long. 
af Fig. 2 In fig. 1 the line found by Reepy is 
drawn. the dotted line is the calculated 
one of AgBr in 10-5 n. KBr, in which 
the scale of. the current densities is 
chosen so that a point of the calculated 
line coincides with a point of the found 
line. 
It appears that there exists a satis- 
3 factory agreement between these two 
o4 05 ob Ves. lines, when it is borne in mind that 
1) Z. f. physik. Chemie. 46 (1903) 602, 
