Absorption Spectra of Dilate Solutions. 



135 



Table VII. Electrical Conductivity of Copper Acetate Solutions. 



At 14-1. 



/* - 139-6. 



V = vol. in litres in which 1 gram molecule Cu(C 2 H 3 O 2 ) 2 is dissolved. 

 /* = molecular conductivity. 



* = (TZ^y- 



a = = fraction of the copper acetate dissociated into ions. 



Moo 



seems probable then that just as the dibasic acid first split off one 

 hydrogen atom as an ion and then the second, so the copper acetate 

 splits up first into the ions Cu(C 2 H 3 O 2 )and(C 2 H 3 2 ),and then the ion 

 Cu(C 2 H 3 2 ) breaks up, after the first process is fairly complete, into 

 the ions Cu and (C 2 H 3 O 2 ). Calculated from the numbers for the 

 electrolytic conductivity given above the quantities of the salt dis- 

 sociated in the two solutions in Table V are 



Cone 0-003748 = 65 per cent. 



0-0007144 = 85 (extrapolated). 



These two solutions will accordingly contain the ions Cu and 

 Cu(C 2 H 3 2 ), the greater the quantity of the latter the more will the 

 colour of the solution differ from the normal. The addition of acetic 

 acid to the solution diminishes the dissociation of the copper salt,, and 

 so increases the difference of the colour from the normal. 



Salts of Vimtrophenol, C 6 H 3 (N0 2 ) 2 OH (2.4'1). 



The dinitrophenol used was the ordinary one ; the specimen 

 obtained from Kahlbaum melted at 114 115. The potassium and 

 ammonium salts were prepared from it. They both crystallise very 

 well, the former in orange, the latter in bright yellow needles, and are 

 therefore easily obtained pure. 



The potassium salt lost on prolonged heating 



to 100 3-95 per cent. H 2 0. 



Calculated for C 6 H 3 (N0 2 >,OK + H 2 3*9 



VOL. LVII. L 



