( 643 ) 
So the coincidence of # and D in a critical point solid-liquid 
wae) 
will take place somewhat above 75°. 
Finally we calculate 7’= 80 (fig 31) for this purpose. Then 9 —=5 
and 
a 2700 
log’® B = 2,467—0,4343p — log’p ; p= 320y ———, 
RR v" 
which gives rise to the following table. 
1 == 80 
p log’ UAE ORE EL p 
| | 
| 
i —1.418 0 192 1.181 1935 305 
6 —0.917 0.229 1.275 1661 259 | 
ED 
5 —0. 404 0.532 1.419 1341 259 | 
4 0.128 0.757 4 5598 1057 223 
3 0.687 0.914 1.774 858 | 102 
2 1297 0.976 1.982 687 — 41 
I 2.033 0.995 2.495 434 —114 C 
0.5 2.551 0.998 8.497 221 — 61 
So the coincidence takes place at exactly 80°. 
If we now examine the foregoing tables, it appears (see fig. 23), 
that the whole curve of coexistence solid-liquid extends from T=62, 
p = — 200 (the point Q) to 7 = 80, p= 259 (the point Or). | Only 
the part above S, (7'= 70), p=0), however, is realisable. 
The triple-point S lying at 70°, and the eritical temperature vapour- 
liqnid being = 133°, we have here: 
Pye KO 
= — = 0,58, 
Pe A od 
which is in perfect harmony with the value which was found for 
it in many cases. 
We remind the reader that for this relation (provided 7, does not 
lie too near any critical point) the general equation [see V, p. 461, 
formula :27a)]: 
Be a7 Ab B 
zm {| ———]: log | ——.— 
TN WD 7 \ 45°" 28 
holds. 
With 46 == 05, 6, 1; b, = 1,5: this becomes: 
Tanen 2 =) 
a = 35 * log 
DRL 98 
