the Concentration of Hydrogen Ions in Solution. 
339 
To test the method, experiments were made with an — HC1 
solution. Four experiments gave 2 95, 2 75, 2*95 and 295 c.c. 
of carbon dioxide respectively. Taking the mean we get for 
the concentration of hydrogen ions x = 049. The value obtained 
from Krannhals’ measurements of the conductivity at 100° C. is 
x = '047 5. The two methods therefore give concordant results. 
Strength of 
H 2 S0 4 used 
Volume of C0 2 
from *1 gm. 
c i i 
ax = — - 1 
c 2 
x from con- 
ductivity 
a 
ol ^5 
2*42 c.c. 
313 
•06 
52 
N 
15 
3'17 „ 
2-15 
•043 
50 
N 
20 
3-87 „ 
1-58 
•0335 
47 
N 
3b 
4-88 „ 
1-05 
•023 
46 
N 
6b 
5-95 „ 
•68 
•013 
52 
N 
120 
6-85 „ 
•46 
•007 
65 
N 
00 
8-5 „ 
*18 
0 
I 
00 
The authors are making similar experiments with other deriva- 
tives of oxalacetic acid and are also investigating the velocity of 
the reaction. In conclusion they wish to thank Mr Fenton for his 
kindness in allowing them to proceed with this work, and Pro- 
fessors Liveing and Dewar for kindly placing the resources of 
their laboratories at their disposal. 
VOL. xi. pt. V. 
25 
