308 



DIRECT PROPERTIES OF MOLECULES 



112 



while for the following acids we have : 



Here, too, the deviation is the greater the higher the mole- 

 cular weight and the greater the number of atoms in the 

 molecule. 



Winkelmann's diffusion experiments on a series of 

 esters afford a rich material from which we may draw an 

 answer to the question in hand. They give : 



Values of Q. 



As before, the column of numbers marked ' observed ' 

 are deduced from Winkelmann's experiments on diffu- 

 sion, and are taken from L an do It and Bernstein's 



1 Another observation gives 87500. 



2 Another observation gives 88400. 



