EQUATION AND THE NATURE OF COHESION. 35 



These are the only two values T have been able to calculate. 

 The value from the gravitation with 8 valences to the molecule, 

 a = N 2 (mH X ValjMf* = 2,99 X I0 12 . Van Laar's value is 2.2] 

 which again is 20 °l too low. 



6. Nitrous oxide. 1\' 9 (). 



{a), a = 2.03 BT c Vjl.M - - P C F C 2 . P c = 71.65 ; T c = 309.5 

 (Cardoso and Arni) d c = 0.454 (Villard) S = 3.658. 



V c = 99.41 a = 4.21 X 10 u 



(b). a = 0.5 P C F C 2 a = 4.43 X 10 2 



(c)i).a = J/y 4.185 X 10 7 /3 d,f fi . p' = 88.3 . . a = 4.04 X 10 12 



{d). a = CRT, V c . C' = 1.513 a = 3.77 X N>' 2 



(e). a = 2>s>ri A AfX ] ' A T^l {d— n){T r — Tfi\ sat 

 — 24° = 9.92 dynes (Verschaefelt). 

 d= 1.0254; D = 0.417; sv 213 =12 1.59 a = 4.10 X 10 12 

 The mean of these various values is 4.12 X 10 12 but in view 

 of the fact that one is so extremely different from the others we 

 may omit 3.77 and the mean is then 4.20 X 10 12 which I think is 

 probably not many per cent from the true value. 



If there are 4 valences in the molecule, the oxygen being biva- 

 lent the nitrogen monovalent the value computed would be 3.59. 

 If there are five valences then the value is 4.29 X 10 12 which agrees 

 well with the found value. Van Laar's value is 3.56 which is 

 again evidently some 20 °/ too low. The' computations indicate 

 that there are 5 valence electrons in the molecule. 



7. Carbon dioxide. f'0 2 - 



(a), a = 2 . 3 BT C Vj 1 . 3 — i>,. V 2 . T c = 304.35; P c = 72, 8 5 ; 



£ = 3.59; r c = 95.42; d c =A6l a = 4.29X10 12 



(/,). a = 6.5 P C V? . a = 4.37 X 10 12 



( C ). a = [jJJP/Sd^. ia' = 95.2 M = 44 a = 4.32 X 10 ' 2 



(r/). a = C'RT c r e . C' = 1.762 a = 4.27 X 10' 2 



(<?). a=CMN^d l l .\d l> . d„ = 1.725; N il:i = 

 8.463 X 10 7 ; C of liquid C0 2 by Eötvös 

 is 2.34 a = 4.61 X 10 2 



!) The factor 4.185X10" in the (c) formula has generally been omitted in the for- 

 mula as written in the pages which follow, but it has of course always heen used. It 

 is the factor for converting' calories to ergs, the value of ft' being given in calories. 



D 3* 



