Number of Electrons in the Atom. 



721 



Hence 



(=)'<■ 



m+l 



■r m ) = AS.+1 — A?„ = C, 



where C is a constant which should be the same for all series 

 of similar elements. 



Also (r m+1 — r M )* = v 



approximately so that 



p 3C 8 



According to the theory therefore we ought to be able to find 

 the number of electrons per atom from the atomic weights. 



Y ,/k/ 



la 





& 



tf 



it 



^3456 

 Order in Series. 



In the figure the values of A ;i for series of similar elements 

 are plotted against the order of the elements in the scries. 



