2 Lapworth, Latent Polarities of Atoms 



and every acceptable test of this kind leads to the same 

 inversion of the customary application of the terms " positive " 

 and "negative" to these two groups. The writer would 

 propose the term "basylous" for such a group as -NH 2 

 which tends to lower the acidity of a molecule of which it 

 forms but a part, and the term " acylous " for a group such 

 as CH 3 'CO- which has the opposite effect. Thus — NH 2 , 

 — NHAlk., etc., are basylous, but almost invariably exhibit 

 positive polarity when attached to carbon ; — H is basylous 

 and usually positive; —CO — , -S0 3 H and --N0 2 are 

 strongly acylous but usuallv positive; while -OH, — OAlk., 

 etc., are acylous and negative. Halogens are acylous and 

 normally negative, but are positive when contrasted with 

 -OH or -NHL. 



CI — OH 



and 

 CI — H 



+ 



< — ■> 



CI 



OH 



1 



and | 



CI 



H 



CI — NIT 



and 

 HO — H 



— + 



( CI NE 

 ■I and 



HO H 



Compounds containing positive acylous groups yield acids 

 by union with negative hydroxy 1, and those with negative 

 basylous groups yield bases with positive hydrogen (or 

 + 



H + H 2 0). In the following pages the terms positive and 

 negative are restricted to the application above indicated. 



The writer originally fell into the habit of labelling the 

 atoms in reactive molecules with + and — signs as the result 

 of his applications of the ionic theory to the reactions of 

 carbon compounds, and especially to those of ketones and 

 allied carbonyl compounds. Thus it was evident that the 

 addition of electrolytes to the carbonyl group invariably 

 proceeded as if the carbon atom were more positive than the 

 oxygen atom, and invariably selected the negative ion ; for 

 example, . 



+ - : 









>c = o 





>C- 



-0 



and 



— > 



| 



| 



CN— H 





CN 



H 



+ 









