Ill 



There is certainly no need lo state explioKly liiat only a sketch 

 has been given in (he above. It seemed, however, desirable to me 

 to test KossEi.'s and Lewis-Langmuir's hypotheses by the simplest 

 atom that can be bonnd both polaily and non-polarly to other atoms, 

 for it is to be expected here that the complex compounds will 

 be built u[) ill the least complicated way. 



Complications occur in the elements of the second period, e. g. 

 Al, Si, and S, as appears from the existence of compounds as 

 Na, A1F„, Kj Si F, and the derivatives of the hexa-valent sulphur. In 

 connection with the above it would have to be assumed that these 

 atoms try to bring together six pairs of electrons in their outer 

 shell, which then possibly might have to be ascribed to the intluence 

 of the electrons of the first spherical shell on those of the second. 

 Before this can be examined more closely, the phenomena referring 

 to the simplest elements will tirst have to be more fully cleared up. 



In the case of boron it is, indeed clear, that as regards the 

 formation of compounds pairs of electrons play an important part, 

 and that especially the non-polar bond, i. e. the bond that does not 

 conduct electrically, is brought about by such pairs. If it is further 

 borne in mind that the latter kind of bonds is much less reactive than 

 the former, it is natural to suppose that the difference between polar 

 and non-polar bond consists in a greater closeness of the latter. The 

 non-|iolar bond might l)e compared to an elect lo-magnet with a 

 well-closed armature or a toroid, whereas in the polar bond the 

 armature is removed or the toroid opened. 



A similar image might be applied to the action of catalysts, 

 in which it is likewise assumed that closed bonds are opened, 

 which gives rise to a greater chance of interaction when meeting 

 other molecules. 



Delft, Dec. 1922. 



