of Homologous Compounds. 



T.\BLE I. 







Boiling-point (abs. temp.). 





Para Hi n. 

























Observed. 



Calculated. 

 Ramage. 



Difference. 



Calculated. 

 Young. 



.Difference. 





c 



O 



o 



o 



o 



CH 4 



1083 



105-7 



-2-6 



106-75 



-1-55 



2 H e 



1800 



1773 



-2-7 



1777 



-2-3 



C\ 3 H S 



2280 



231-9 



4-3-9 



229-85 



4-1-85 



: C 4 H 10 



2740 



275-6 



4-16 



272-6 



-1-4 



C 5 H 18 



309-3 



312-2 



4-29 



3094 



4-01 



O e H 14 



341 -95 



343 9 



4-195 



341-95 







7 H ie 



3714 



372-3 



4-0-9 



371-3 



-o-i 



CH, 



398-6 



398-3 



-0-3 



398 1 



-0-5 



9 H 20 ... 



422-5 



422-5 







422-85 



4-0-35 



C l0 H oo ... 



4460 



445-2 



-0-8 



445 85 



-015 



C xl H. n ... 



467-0 



466-8 



-0-2 



467 35 



4-0-35 



C 12 H 2C ••• 



487-5 



487-3 



-0-2 



487-65 



+015 



13 H M ... 



507 



507-0 







506-8 



-0-2 



C U H 



525 5 



5260 



4-0-5 



525 



-0-5 



15 H 32 ... 



5435 



544-2 



4-0-7 



542-3 



-1-2 



^16^34 • • • 



560-5 



5619 



4-1-4 



558-85 



-1-65 



C K H 3 , ... 



576-0 



5790 



+ 30 



574-7 



-1-3 



C H H, S ... 



590-0 



595-7 



4-5-7 



589-9 



-0-1 



1 C 13 H l0 ... 



6030 



611-9 



4-8-9 



604-5 



+ 1-5 



It may be noticed especially that the agreement is much 

 better in the case of those boiling-points which are likely to 

 have been most accurately determined, notably pentane, 

 hexane, and heptane, and that the differences between the 

 calculated and observed boiling-points above 570° abs. are 

 not nearly so marked. 



Consider now the replacement of a terminal atom of 

 hydrogen in each normal paraffin b} an atom of chlorine, so 

 as to form the homologous series of primary alkyl chlorides. 

 The boiling-points of these chlorides are much higher, and 

 the differences, A, are much lower than for the corresponding 

 paraffins, but the gradual fall in the values of A as the series 

 is ascended is unmistakable. The same remarks apply to the 1 

 bromides and iodides, the boiling-points being still higher 

 and the values of A lower. 



But the point of chief interest is that most of the values 

 of A for the halogen derivatives may be calculated without 



great error from the formula 



A = 



144-86 



T 0-0148 v'T 



which was derived from the boiling-points of the paraffins 

 themselves. The first calculated value of A, as will be seen 

 from Table II.. i- decidedly high in each series (avera 



B 2 



ge 



