132 
MESSRS. W. R. BOUSFIELD AND C. ELSPETH BOUSFIELD 
therefore sufficient to make up solutions of approximately the strength required and 
calculate the exact strength from the densities. To secure accuracy in the con¬ 
centrations the densities were taken in duplicate, the means of the two determinations 
at 20° C. being used for the determination of the concentrations. The mean observed 
values of the densities are given in Table VI., together with the values of P and h 
calculated from the values of p 2n . 
Table YI.—Densities of KC1 Solutions. 
No- of 
solution. 
P. 
h. 
Pi' 
P-20■ 
Pss- 
I. 
20-188 
16-362 
1■13907 
1• 13427 
1-12878 
II. 
14-821 
23•785 
1•10034 
1-09618 
1-09111 
III. 
10-495 
35•296 
1-07030 
1-066725 
1•06205 
IV. 
7-150 
53-743 
1-04752 
1-04445 
1-04010 
V. 
3-667 
108-72 
1-02416 
1-02172 
1-01777 
VI. 
1'860 5 
218-30 
1-01219 
1-01011 
1-00636 
Water 
o-o 
oc 
0-99993 
0-99823 
0-99473 
The NaCl solutions were derived from a 25 per cent, solution very accurately 
made up, from which solutions II., III., and IV. were made up by weighing. 
Solution V. was made up by weighing to be as near normal as possible, and VI. 
and VII. were also made up by weighing to be as nearly as possible half and quarter 
normal. But no use is made of the volume concentrations in this paper, since they 
differ at the different temperatures. The quantity h, which represents the number 
of molecules of water per molecule of solute, is the more useful. The densities of 
NaCl solutions were not taken in duplicate. The observed values are given in 
Table VII. 
Table VII.- — Densities of NaCl Solutions. 
No. of 
solution. 
P. 
h. 
P7- 
P20■ 
P33- 
I. 
25■000 
9-7347 
1-19538 
1•18879 
1-18188s 
II. 
18-945 
13-883 
1 •14531 
1-13952 
1-13323 
III. 
13-519 
20-758 
1-10238 
1-09745 
1-09178 
IV. 
10-005 
29-189 
1-07519 
1-07094 
1-06576 
V. 
5-625 
54-442 
1-04183 
1-03857 
1-03404 
VI. 
2-8669 
109-94 
1-02129 
1-01873 
1-01468 
VII. 
1-4476 
220-91 
1-01073s 
1-00858 
1-00482 
Water 
o-o 
GC 
0-99993 
0-99823 
0-99473 
