the Shape of the Molecule. 



449 



7) with temperature do not furnish any information as to the 

 change of shape of the molecule with temperature, because 

 we do not know to what extent cr l depends on the field of 

 force round the molecule. The same also applies to the 

 variation of the coefficient of diffusion with temperature, 

 because this also depends on o- l5 the radius of the sphere of 

 action. 



Table II. 



1 



w/ 2 ■ 



(Sm 1/3 ) 



2m 1/2 "; 





3/2 



( 1 s\ 3 / 2 

 (z™ 1 3 ) 



H, 1415 HCl 

 CO 1-414 ! CI, 

 NO 1-412 H,0 

 0, 1-415 HjS 



1-276 00 a 



1-416 N 

 1-601 ; S6 2 

 1-522 ! CH 4 



C 2 N 2 



: 



1-712 NH 3 

 1-729 C 2 H 4 

 1-726 CH3CI 



2-116 N 2 

 2004 C H 5 C1 



1-865 

 2-301 



2-023 

 1-410 

 3-874 



Methvl alcohol CH 4 



Ethyl alcohol C 2 H e O 



9-80° Formic acid CH o 2 



3-240 1 Aoeticacid C 2 H 4 2 



g.tjQQ ; Propionic acid C 3 H B O a 



3.975 ' Butyric acid C 4 H 8 2 



4-294 lovalerianic acid . . . C 5 H 10 O 2 



2-116 

 2656 

 3109 

 3-505 



3-849 



Propyl alcohol CgH^O 



Butyl alcohol O 4 H 10 O 



Isobutyl alcohol ... C 3 H 12 

 Amyl alcohol C 6 H 14 



Methyl formate C 2 H 4 2 



Methyl acetate C 3 H 6 o 



Ethyl acetate C 4 H 3 0., 



Ethyl propionate ... C 5 H 10 O 2 

 Ethyl butvrate C 6 H 12 0, 



2656 Iodo benzene C 6 H 3 I 



3-109 ' Bromo benzene ... C 6 H 5 Br 

 3505 ,| Chloro benzene ... C G HlCl 



3-862 ■ ! Fluor benzene C 6 H 5 F1 



4-189 Pentanfl D.TT. 



3-134 

 3230 

 3-259 

 3-289 

 3-875 

 3-821 

 1000 

 1-416 



Ethyl valerianate ... C 7 H u 2 ! 

 Isobutyl butyrate . . . C 8 H 16 2 

 Isobutyl valerianate C 9 H l3 o i 

 1 



4-494 

 4-778 

 5046 



Octane . 

 Mercury 

 Iodine . 



C sH lS 



Hg 



I 2 



1 



One point calls for remark at this place. The law of force 

 surrounding a molecule is usually determined from the 

 variations of the coefficient of viscosity or diffusion with 

 temperature, on the assumption that the molecule behaves as 

 a centre of force. But this assumption is objectionable 

 since a molecule or an atom must possess an actual volume. 

 The writer * has shown that if the atom is spherical in 



shape the cross-section is proportional to mV^i.e., if a t 2 



2 



represents the true cross-section of the molecule, —^ is 



J- m l,6 



constant. This is approximately realized. On the other 

 hand the chemical attraction of one atom on another is 

 considerable, and must influence the apparent radius <r l of a 

 molecule. Thus the writer has shown that this attraction is 



* Loc. cit. 

 Phil. Mag. S. 6. Vol. 20. No. 117. Sept. 1910. 



2H 



