of Homologous Compounds. 



17 



That the observed boiling-points of many of the alcohols 

 are far from accurate seems to be proved bv the results given 

 id Table IX. 



Table IX. 



Differences between the Boiling-points of Isomeric Alcohols. 



Formula. 



Normal, 

 Primary and 



Secondary. 



Primary. 



Normal and 



Iso. 



Iso-primary 



and Normal 



Secondary. 



C.H.OH 



+ KV9 

 +190 



+220 

 + 11-5 



+ 8-85 

 + 5-95 

 + 8-0 

 + 120 



+ 8-05 

 + 13-05 

 + 14-0 

 - 0-5 



C,H u OH 



C c H )3 OH 



C 7 H n OH 



Moan 



17-35 



87 



8-65 





One would expect, probably not constancy, but at any rate 

 some sort of regularity in each series, and the violent 

 fluctuations must certainly be due to experimental errors. 

 The conclusion already arrived at, that the observed boiling- 

 point of secondary heptyl alcohol is much too high, and 

 that of isoheptyl alcohol much too low seems to be confirmed. 



The mean differences between the calculated and observed 

 values of A are given in Table X. 



Table X. 





Lower Members. 



Higher Members. 



Homologous Series. 



No. of 

 values 

 of A. 



Mean diff. 



between 



calc. & obs. 



values of A. 



No. of 

 values 

 of A. 



Mean diff. ' 

 between 

 calc. & obs. 

 values of A. j 



Cyanides, K—CN 



Nitro-compounds, R — NO„. . . 

 Ketones, CH^— CO— R ..?... 



Acids, R—COOH 



Alcohols, R . OH :— 



(1) Normal primary 



(2) „ secondary 



(3) Iso-primarv 



1 



1 

 o 



o 

 T 



1 



+ 12-65 

 + 11-10 

 + 6-20 



+ 5-S7 



+ 12-87 

 + 10-65 

 + 2-05 



4 



1 

 3 



7 



7 

 4 

 2 



+290 

 +3-S5 



+2-85 

 + 1-58 



+ 371 

 +474 

 +7-65 ? 





Total 



10 



+ 9-12 



28 



+3-40 





It will be seen that the differences between the calculated 

 and observed values of A are considerably greater for 

 ritll Mar,. S. 0. Vol. ( J. No. 49, Jan. L905. 



C 



