AQUEOUS SOLUTIONS.—McKAY. 355 
most of the signs being negative. The results of these measure- 
ments seem to show that at such dilution the double salt is 
separated into its components. 
The conductivities of the strong double salt solutions seem 
to he greater than the conductivities of corresponding mixtures, 
though in the case of dilute solutions they agree. 
A fact which makes the writer somewhat suspicious of the 
trustworthiness of the measurements of the mixtures of strong 
solutions is that the density of these mixtures was found to be 
less than the mean density of the constituent solutions, amount- 
ing at the concentration 0.8 to a difference of 0.1 per cent. 
The error of a density measurement might be 0.03 per cent. The 
density of the double salt solutions was found to be equal to the 
mean density of the K,SO, and MgSO, solutions of the same 
strength. The following are the measurements on which these 
statements are based. With the exception of those for the 
MgSO, solutions, the values of which are taken from Kohlrausch 
and Hallwachs’ determinations, they were made by the writer. 
1 KeS0q. + MgSOx. Double Salt. qo ee 
| 
pga emcee Oo per eec Pais er eae 
.8327 =| 1.0567 |, 1. 1.05863 | 1.001 | 1.0633 | .8019 | 1.0503 
7975 =| 1.0589 5) 1.02987 | .8345 | 1.0531 | .6690 ! 1.0422 
.6688 | 1.0456 .20 1.01518 | .6688 | 1.0427 | .5003 | 1.0317 
5029 | 1.0344 O1 L-00063;| .o744 | 1.0243 | 222-52.) Yotee: 
SOULO oh 0840) |}. o..04 0998) |, 1/0040) |S cote aenne 
Poem MCOL GS! le ctc:cvoe tl") <r-ls'e16 {02004 5 0015s) aenlieeeere 
OID TS | ALOO0G: |) 2c. [fs entre BOTOOE TU OME | erercrrete eerecrye 
The results of the double salt measurements lead the writer 
to conclude that in dilute solutions the double salt entirely 
separates, but that in strong solutions the two component salts 
are at least partly united. 
