-H 



Lapworth, Latent Polarities of Atoms 



The ketonic form (i) is devoid of acid properties, or, in 

 other words, the hydrogen atom is not directly ionisable. 

 Under the influence of the •' key " oxygen atom, however, it 

 is endowed with some additional positive polarity. In the 

 structure (ii) we have a rearrangement of the partial valencies 

 analogous in all fundamental respects to Thiele's expression 

 for conjugated systems, the relation between (i) and (ii) being 

 the same as between 



.C = C 



,c=c 



and 



.CJ— O 



In (ii) the hvdrogen atom attains only what may be termed 

 incipient ionisation (in other words, a polar character with 

 partially diffused valency), but in virtue of this is able to 

 attract the negative hydroxy 1 ion. The subsequent changes 

 leading to the formation of non-ionised water and the kation 

 of the enol form in (vi) are now obvious. 



No difficulty whatever is found in figuring the non-ionic 

 analogue of any of these stages. Thus (vii) may be developed 

 as the non-ionic form of (iv); and here again the diffuseness 

 of the partial valencies of the metallic radicle and the acid 

 radicle is consistent with what has been emphasised in the 

 preceding paragraphs. 



The formulae given in Fig. 3 illustrate as fully as can be 

 done within a limited space some of the applications of the 

 principles in the aromatic series. 



(«•) 



Y 



+ j. 



— Y 



(e) 



H 



+ 



+J R 



Hi* 



+ 



H 



3 



4* 

 ft 



Fig. 3. 



>|H 



_ + 

 H 



