CHEMISTRY 199 



H H 



I I 



-C- [-C-] 



C-H 

 I 

 C-H 



H- 



I 

 H 



H-C-H 



I 

 H 



In each of the compounds represented by 

 these formulas every carbon atom is believed 

 to have four valences and every hydrogen 

 atom one. 



As the number of carbon atoms in the mole- 

 cule increases the number of possible forms, 

 isomers so called, multiplies with great rapid- 

 ity. Of compounds C 7 H 16 there are 9 forms; 

 for C 8 H 18 , 18; for C 9 H 20 , 35; for C 10 H 22 , 75; 

 for CnH 24 , 159; for C 12 H 26 , 355; for C 13 H 28 , 

 802; and for Ci 4 H 30 , 1855 possibilities. 1 There 

 can be no reasonable doubt that the prepara- 

 tion of each and all of these compounds would 

 be possible, and that once formed they would 

 be very stable substances. In truth, no one 



1 Cayley, Berichte, 8, 105fi (1875). F. Hermann, Berichte, 

 13, 792 (1880) ; 30, 2423 (1897) ; 31, 91 (1898). Losanitsrh, 

 Berichte, 30, 1917, 3059 (1897). "Optical isomers" are dis- 

 regarded in the estimate. 



