376 Proceedings of Boy al Society of Edinburgh. [sess. 
I. 
Acetic acid . 
Malonic acid 
Depression. Concentration. 
0*0950 0-04965 
0-0977 0-04483 
Acetic acid . 
Malonic acid 
0-0986 0-0517 
0-0935 0-0431 
Calculated from, these numbers we obtain the ionisation values 
0'158 and 0*156 respectively. From the conductivities we obtain 
the values 0-162 and 0’164. Although these numbers are some- 
what more divergent than in the previous instance, still they do 
not lie beyond the estimated error of the experiments. 
Experiments with Strong Electrolytes. 
Having thus shown that in the case of malonic acid our method 
gave results sufficiently in accordance with the electrical method, 
we now proceed to give the freezing-point experiments for strong 
electrolytes for which previous observers had obtained results 
which were not accordant with the ionisation values obtained from 
the conductivities. 
Hydrochloric Acid, HC1. 
Concentration. Depression. 
Cone, of Acetic 
Acid. 
Depression. 
Ionisation. 
0-05141 0-1847 
0-0970 
0-1848 
0-909 
0-05219 0*1870 
0-0970 
0-1844 
0-908 
Potassium Chloride, 
KC1. 
0-0527 0*1841 
0-09757 
0-1856 
0-858 
0*05275 0-1839 
o-iooo 
0-1907 
0-850 
Sodium Chloride, HaCl. 
0-0519 0-1829 
0-09668 
0-1840 
0-874 
If now we compare these ionisations with the values deduced from 
the conductivity method, 
we obtain the following table for 0'05 
normal solutions : — - 
HC1. 
KC1. 
NaCl. 
From conductivity at 18° * 
0-937 
0-895 
0-874 
,, ,, o°t 
From freezing point 
0-956 
0-892 
0-877 
0-908 
0*854 
0-874 
* Kohlrausch und Holborn, 
Leitvermogen der Electrolyte, pp. 
159, 160, 200. 
t J. G. MacGregor, Trans. Roy. Soc. Canada , 1900-1, pp. 6, 7. 
