495 



66,03 X 1156 

 Tk = -1^- = 4920° abs. 



The melting point, lying at 1426° C. = 1699° abs. (98,97, Si) 

 according to Doerinckkl (1906), Tk: 7% would be = 2,90. 



If we repeat the above check-calculation (§ 2), it follows (2/ 

 becoming = 1 -f- 0,04 X 70,2 — 381) Ihat 

 3,81 X 28,3 107,8 



^" ^ 155. 10-5 X 22m = 34:74 " — (^^^^'"'^'^^) 

 This value seems somewhat too high, as at the ordinary tempe- 

 ratuie for Si values have been found in the neighbonihood of 2,50 

 (WöHi.KK gives 2,49; in Rudokf's book on the [)erio(iic system we 

 find 2,48; etc.), but these earlier values may be too low. 

 For /)k we find with P. = 0,816 (see above): - 

 0,0302 y 1156.10-4 



pjc = ■ — = 1450 atm. 



^ 240,25.10-8 



If we assume the value 1,6 for the ratio 7\ -. 7\, Ts (the boiling 

 point) would be about 3080° abs. V. Wartknbkhg's value 1902), 

 viz. >1205'C. (the melting point n.b. lying as high as 1426° C.\ 

 is therefore rather euphemistic. 



The value /.^" = 3,161 : 0,6 = 5,27, hence ƒ, = 12,1, would 

 correspond with 7', := 3100°. For//, may be expected ƒ/, = 87 = 15,2, 



4. Germanium. With l/ak=Se. 10 -2 we find (;i = 0,835, as 

 2y is = 3,58), bk being = 210 . 10 & ; 



67,56 X 1296 

 Tk = —T,~7r— = 4170° abs. 



According to Biltz (1911) the melting point lies at 958° (J. = 

 = 1231° abs., hence 7'/c : 7V would here be =: 3,39. 



For 2y is found 2y = 1 -|- 0,04 x 64,6 ="^58, so that we 

 calculate : 



3,58 X 72,5 259.6 



^» = 210.10/22412- = ï^ = M^- (calculated) 

 Winkler found 5,47 for 20° C, so that the agreement is again 

 striking. 



We further calculate for pk'. 



0,0309 X 1296.10-4 



^' = 441.10-8 = ^^0^^^. 



With 7';fc:7; = l,6 we should find about 2600° abs. for 7\. 

 RuDORF gives 7', > 1300° C. Remark as above for Silicium. 



For /JO we calculate 2,959:0,6 = 4,93, hence /, = 11,4, while 

 fk would be = 14,3. 



