141 



then we should find quite improbable values for ak and bjc ^). 

 We calculate for j^k- 



log pk = 0,1877 + 2,0668 = 2,2545, 

 i. e. 



pj;. = 180atm. 

 In order to get somewhat more certainty concerning the values 

 of Tk and p^., and also of ]/ak and bk, we can still make the 

 following calculation. 



From /rfc=:3080, /-{- log pk = 4:, 8S0 follows namely with ƒ 

 resp. = 2,5, 2,6 and 2,65 : 



ƒ =2,50 

 2,60 

 2,65 



From 8?2 . bk = RTj, -. pt follows then with ?z = 2, H = l: 273 

 for bk (per Gr. atom) k- = 71- •• 4370 ;;a;, i.e. bk resp. = 117, 142 

 and 156.10-5. 



With these values for 6^. we get then ok resp. ^ 95,2, 111,3, 

 119,6 . 10—*, i. e. \/ak (per Gr. atom) resp. = 9,76, 10,55 and 

 10,94.10-2, from Tk = If^l,^ ak-bk- 



It appears from this most convincingly that — as bk must lie in 

 the neighbourhood of 150 . 10-^, \/ak in that of 11. lO"' — the 

 value 1232 abs. is pretty well excluded for Tk, and that we have 

 therefore the choice between from 1185 to 1162. Retaining 

 6a: = 150. 10-^ we get i/^a == 10,77 . 10— 2, as we assumed above 

 (rounded off 10,8), and further : 



rA: = 1172 abs. = 899° C. ; pk = l^^ atm . 



But it is also possible that Tk becomes somewhat higher, e. g. 

 1185°, to which corresponds p^t = 191 atm. Then the value o\' \/ak 

 would, however, be still lower than that which we calculated from 

 Hg I„ viz. 10,7 . 10-' (loc. cit. p. 8), and that of bk would become 

 :=142.10-^ i.e. equal to that which was calculated from this 

 same compound. Bui these were the very lowest values. Those 

 which were calculated from Hg Cl^ and Hg Br^, were both higher 

 (loc. cit. p. 8). 



1) With regard to the value of a, I have convinced myself that from the com- 

 pressibility of mercury at 0°, 110°, and 192° C. follows about the same value of 

 a as was calculated from the mercury halides for ak. And with regard to hk, 

 even on the supposition that Hgo for liquid mercury lias the stoechiometric pro- 

 perties of mercuro compounds, a value would follow from the densities of HgaClg 

 and HgaBrg for Hg (per Gr. atom) in Hgj, which is only little less than was 

 found for Hg in the mercuri compounds, (viz. about UO . 10-5 instead of 150 . 10-^). 



