656 
Proceedings of the Koyal Society of Edinburgh. [Sess. 
Solubility in Water at 25-2°. 
Total acidity = 
Free base = 
Salt = 
Free HCI - 
ki, 
I. 
Water. In 
■04137 N. 
•04137 
Total HCI - Salt — 
x -0515 
— HCI. 
16 
1554 N. 
•04137 
•0515 
•0110 N. 
113-2. 
K 
•0110 x -0413 
7 
i— i 
i— i 
III. 
N 
N 
N 
Water. 
16 HC1 - 
Water. 
25 HCL 
16 HCI- 
Total acidity 
. -04315 N. 
•1551 N. 
•03723 
T106 
T493 
Free base 
• • . • 
•04315 
• • • 
•03723 
•03723 
Salt 
• • • • 
•05110 
... 
•0317 
•04957 
Free HCi 
• • • 
•00975 
•01007 
•01293 
• 
121-4 
85-2 
103-0 
K 
• 
N 
32 
HC1 was also used in this way and gave still lower values of 
h 
K' 
The Rate of Catalysis of Diazo-acetic ester by nitric acid is a 
possible method of estimating the concentration of liydrion, and there- 
fore the hydrolysis in a solution.* It was found on investigation to 
give quite reliable results, and was therefore used to estimate the 
hydrolysis of anthranilic nitrate solution. The hydrochloride could 
not be used for this catalysis on account of secondary reactions with 
the ester. 
About T of a gram of diazo-acetic ester was weighed out and dis- 
solved in a known volume of water in a small flask. A small quantity 
of the acid or nitrate solution was put into the flask in a small test-tube 
to avoid any mixing of the liquids. The flask was immersed in a 
thermostat at 25° C. and connected to a gas-burette in a water-jacket 
at room temperature. 
When the volume of the contained air was steady, the liquids in the 
flask were mixed, and readings of the volume were taken every few 
minutes. The velocity constant was calculated for a reaction of the 
first degree. In the nitric acid catalysis, enough potassium nitrate was 
dissolved in the water to reproduce the conditions in the solution of 
anthranilic nitrate. 
* Bredig and Fraenkel, Zeit. fur Electrochemie , vol. xi. p. 525. 
