VARIATION OF MOLECULAR SURFACE-ENERGY WITH TEMPERATURE. 651 
Table I— (continued). 
Ca7'hon tetrachloride. 
(Crit. temp., 283° C.) 
7(M«)i=-. 2-1052 (t- 6-0). 
Benzene. 
(Crit. temp., 288‘’-5 C.) 
7 (AH)J = 2-1043 (t - 6-5). 
Chlorobenzene. 
(Crit. temp., 360° 0.) 
7 (Mt;)f = 2-0770 (-- 6-3). 
7 (Uv)i. 
1 
7 (Mr)i ' 
1 
7 (Mw)i 
i (cent.). 
t (cent.). 
' • 
L j-i u. J• 
T. 
T. 
Found. 
Cal. 
Fonud. 
Cal. 
Found. 
Cal. 
O 
o 
Erg-.s. 
Eras. 
0 
o 
Ergs. 
Ergs. 
0 
0 
Ergs. 
Ergs. 
80 
203 
414-6 
414-7 
80 
208-5 
425-1 
425-1 
150 
210 
423-2 
4-23-1 
90 
193 
393-7 
393-7 
90 
198-5 
404-5 
404 0 
160 
200 
401-3 
402-3 ' 
100 
183 
372-3 
372-6 
110 
188-5 
384-0 
.383-0 
170 
190 
381-8 
381-5 
110 
178 
351-7 
351-6 
110 
178-5 
362-9 
361-9 
180 
180 
360-5 
360-8 
120 
163 
.330-3 
330-5 
120 
168-5 
.341-6 
340-9 
190 
170 
340-0 
840-0 
130 
153 
.309-4 
309-5 
130 
158-5 
.3-20-3 
319-8 
200 
160 
319-1 
319-2 
140 
143 
288-1 
288-4 
140 
148-5 
299-0 
298-8 
210 
150 
298-2 
298-5 
150 
133 
267-4 
267-4 
150 
1.38-5 
278-1 
277-8 
220 
140 
277-0 
277-7 
160 
123 
246-7 
246-3 
160 
128-5 
256-9 
256-7 
230 
130 
256-2 
256-9 
170 
113 
226-0 
225-3 
170 
118-5 
2.35-2 
235-7 , 
240 
120 
234-9 
236-2 
180 
103 
204-8 
204-2 
180 
108-5 
213-8 
214-6 
250 
110 
213-9 
215-4 
190 
93 
183-3 
183-2 
190 
98-5 
193-4 
193-6 
260 
100 
192 8 
194-6 
200 
83 
162-3 
162-1 
200 
88-5 
172-5 
172-5 
270 
90 
171-9 
173-9 
210 
73 
140-8 
141-1 
210 
78-5 
151-9 
151-5 
280 
80 
150-6 
153-1 
220 
63 
118-9 
120-0 
220 
68-5 
131-0 
1.30-5 
290 
70 
128-9 
132-3 
230 
53 
96-8 
99-0 
230 
58-5 
110-1 
109-4 
300 
60 
109-7 
111-5 
240 
43 
76-5 
77-9 
240 
48-5 
89-0 
88-4 
310 
50 
90-3 
90-8 
250 
33 
55-5 
56-8 
250-* 
.38-5 
68-7 
67-3 
320* 
40 
71-5 
70-0 
260 
23 
35-9 
35-8 
260 
28-5 
48-6 
46-3 
333 
27 
46-7 
43.0 
270* 
13 
21-7 
14-7 
270 
18-5 
28-8 
25-3 
360 
0 
0-0 
283 
0 
0-0 
275 
13-5 
19-9 
14-8 
280 
8-5 
9-0 
4-2 
288-5 
0-0 
00 
1 
1 
i 
These results clearly show the validity of the ecjuation — k {t — d) over a 
very long range of temperature ; from 20° C., in most cases, to within 20 or 30 degrees 
below the critical temperatuie. Deviation becomes apparent where an asterisk has 
been placed opposite the temperature. A complete formula, representing- all the 
results with fair accuracy, will afterwards be adduced, but several important deduc¬ 
tions may be drawn from the simpler one. 
3. Conjirmcition of these residts at — 89°‘8. 
Ethyl oxide, methyl formate, and ethyl acetate remain liquid, even when cooled to 
the boiling-point of nitrous oxide under atmospheric pressure. This temperature, 
which we have carefully determined by means of a thermometer filled with pure dry 
hydrogen (‘Trans. Chem. Soc.,’ 1893, p. 833), is — 89°-8. It was thought advisable 
to measure the surface-energy, and to find out whether the linear relation between 
molecular surface-energy and temperature persists even at that low temperature. The 
4 o 2 
