209 



as function of — must lie on a straight line, for every equation of 



the form y =: mx -\- b )'epresents a straight line. Expressed in a 

 graphical representation this appears really to be the case ^), and 

 the course of the lines suggests that the energy-increment is little, 

 if at all, dependent on the quantity of added catalyst. The values 

 of Ink at 0^ fall outside the sti-aight line in the catalysed reactions. 

 As on account of the slight velocity of the reaction at 0° the 

 observations need not be very accurate, I repeated two measurements 

 at 0°, viz. of the non-catalysed reaction, and of that with 0,00178 

 mol. p. bromobenzene sulphonic acid. I extended the observations 

 over fully two days instead of over seven hours. 



temp. 0° 1 mol. diph. 12'/2 mol. anh. 



temp. 0° 1 mol. diph. 12'/2 mol. anh. 

 0.00178 mol. acid. 



Though the values which I found, were indeed lower, the constant 

 of the purely catalj^sed reaction appeared to have the same value 

 as was determined in former experiments, viz. 0,00218 — 0,00160 = 

 = 0,00058 (found formerly = 0,0006). 



lo be expected was a value ' 



(3,1)' 



= ± 0,00132, hence for 



the gross catalysed reaction 0,00J 32 + 0,00160 = + 0,0029 ; a 

 value that exceeds the error of observation many times. 



In FeClj I think I have found a catalyst which is catalytically 

 active undiminished down to 0°. As these experiments have not yet 

 been completed, they will be discussed in a later publication ; 1 may 

 conclude from tlie experiments already made that also ferri-chloride 

 enlarges the "hill" of energy and that accordingly also this catalytic 

 action can alone be explained by the aid of Scheffek's theory. 



1) Diss. Delft 1922. 



