457 



<j. tz=^ — \ 75°,39 = 97,70 abs. Hence m = 0,6485 , 3,424//^ = 2,221. 

 The ^•c^lue of f interpolated from — lot/^" e z=z clc. with ƒ ;= 2,322, 

 gives & = 0,055 J 8. 



« + 5£/2 . „_jj 



^ 



t/i= 2.4960 0.401 j 31.21 0.071 



c/o = 0.02745 1 36.43 !| 0.05894 1 37.67 



0.329 (lig.), 

 -1.24!(ü.) 



Can the clne to the singular behaviour of the vapour perhaps be 

 found in this that Ckommelln has not determined the vapour densi- 

 ties dlrecthj, but that he has calculated them from the law of Boyle? 

 With a too small value of ii one naturally gets then a too slight 

 value of .3 from fi =:n — (3.424 in : e). Then no association need of 

 course be assumed in the vapour, and the impossible values of /?,. 

 below Tk are at once accounted for. The found values of /?,. would 

 then be quite worthless. The question is therefore: where has 

 Crommeli^ begun not to determine the given values of the vapour 

 density directly, but to calculate them from the (not yet valid) law 

 of Boyle ? ') 



A. ^=: — 183°,! 5=89,94 abs. Here />^ = 0,5970, 3,424 /;i = 2,044. 



From lo(/^° 8 =z etc. we lind the value e 

 with /= 2,314. 



0.02742 (/> = 1,3162) 



8-\-5d2 n—0 



(^1 = 2.589 0.386 33.53 



(/, = 0.015091 66.26 



0.02856 



0.061 i I 0.325 iliq.) 

 71.57 -5.31 !(u.) 



We point out that the liquid value duly decreases gradually, and 

 is still higher than ^^ = 0,29 at 2' — 90 (absolute). So there is nothing 

 impossible here ^). 



') Otherwise p = 2,78 would have to be taken here instead of ii,Ü-i, hence 

 f = 0,058 instead of 0,055; or else q.-, should be assumed somewhut smaller, in 

 order to iind at least the value 0,33 (that of the liquid) for ^vaiioui- 



-) A rise of p to 1,44 instead of 1,32 (j to 0,030 instead of 0,0274) — or else a 

 diminution of n^ from 0,0080 to 0,0075 — might reduce /3r to 0,33 here. The 

 first supposition is impossible, for then tl'e value of p at — 183o,15 would be 

 greater than at 183°,01, where 1,34 was found. But a diminution of on by 6% 

 in consequence of an erroneous calculation of ik^ (probably from the law of Boyle) 

 is very well possible. 



