Affinity 



arid Dissected {Structural) Formula. 





a. 



b. 



c. 



Heat- 

 disturbance. 



Ethylic alcohol ... 

 Amylic alcohol ... 

 Cetylic alcohol ... 



- 55 

 + 10 3 

 + 1291 



+57-9 

 57-9 

 57-9 



63-7 



86-2 



106-7 



-120 



-18-7 

 +79-6 



413 



It would hence seem that heat-absorption takes place in the 

 case of lower members of the alcohol series, and heat-evolution 

 in the case of the higher members in this reaction. It may be 

 noted that if the heat- disturbance betaken as —12*0 in the case 

 of methylic alcohol, the value of 28F 100 for the as yet unobtained 

 methylene would be —15*8, or less than that of ethylene, as 

 might a priori be expected, methylene being a lower homologue. 



It may also be noticed that the analogous reaction with formic 

 acid, 



CH 2 2 = CO + H 2 0, 



leads also to heat-absorption, the amount per metrogramme of 

 formic acid being 



27-5 + 57-9-97'2-0-744= -12-5. 



19. Again, when ethers and steam are generated from alcohol 

 in virtue of the reaction 



2 {C n H 2 ^ 1 ) OH = H 2 4 (CT H 2 »+ 1 ) 2 0, 



there is absorption of heat. In this case 77z = 0, and for every 

 two metrogrammes of alcohol the heat-disturbance is given by 

 the equation 



H l00 z=.b + d— 2c; 



where b is, as before, the affinity-value for water, d that of the 

 resulting ether, and c that of the alcohol employed. 





b. 



d. 



c. 



Heat- 

 disturbance. 



Ethylic alcohol ... 

 Amylic alcohol ... 



+57'9 

 +57-9 



+33-0 



+83-5 



+63-7 



+ 86-2 



-36-5 

 -310 



20. When acids and alcohols give rise to water and compound 

 ethers by the reactions 



(O h*»+i) OH + (C» H 2 *- 1 0) OH = H 2 



+ (C n H 2 *- 1 0)0(C w H 2 " +1 ) 



heat is uniformly absorbed; here m = 0, and the heat-disturbance 

 is given by the equation 



H ioo=b + e -(c+f); 



where, as before, b and c denote respectively the affinity- values 



