CHEMICAL PKOPEKTIES OF FATTY ACIDS AND RELATED COMPOUNDS J 15 



hydrolysis which results when one starts with the ester is minor. On the 

 other hand, when K is small, the reverse will be true. 



A number of considerations alter the point of equilibrium. The first 

 factor is the proportion of reactants. If one starts with equal molecular 

 amounts of acetic acid and ethyl alcohol, equilibrium is reached when 

 06.7% of the potential yield of ester is obtained. This can be increased to 

 82% when 2 parts of alcohol are used to 1 part of acetic acid. Further 

 excess of alcohol does not markedly increase the yield, and it cannot be 

 rendered quantitative by this procedure. On the other hand, esterification 

 can be made largely complete Math an excess of alcohol in the acid-catalyzed 

 reactions. Similarly, hydrolysis of the esters to alcohol and acid is rendered 

 almost quantitative when they are acid-catalyzed and when an excess of 

 water is employed. 



A second factor which alters the extent of esterification is the prevention 

 of accumulation of the reaction products. Thus, when high molecular 

 weight alcohols are used, the water separates as a layer and can be re- 

 moved, thus increasing the yield of ester. The addition of calcium chlo- 

 ride or other dehydrating agents will have the same effect in augmenting the 

 yield of ester. 



Another condition which might be expected to alter the speed and 

 equilibrium constant is temperature. However, since the heat evolved in 

 esterification reactions is relatively low, the resulting effect of temperature 

 on the equilibrium constant is minor. The esterification reaction is, how- 

 ever, speeded up when agitation is employed. 



Probably the most important consideration in the equilibrium and 

 velocity constants is the nature of the reacting components. ^^^-'^^"^^^ 

 Menschutkin^^^"^^'^ and others have shown that primary alcohols are most 



^'^ W. Kistiakowsky, Z. physik. Chem., 27, 250-266 (1898). 

 58» V. Meyer, Ber., 27, 510-512 (1894). 



381 V. Meyer and J. J. Sudborough, Ber., 27, 1580-1592, 3146-3153 (1894). 

 '82 J. J. Sudborough and L. L. Lloyd, J. Chem. Soc, 75, 467-483 (1899). 

 383 W. A. Bone, J. J. Sudborough, and G. H. G. Sprankling, /. Chem. Soc, 85, 534-555 

 (1904). 



s*-* J. J. Sudborough and E. R. Thomas, /. Chem. Soc, 91, 1033-1036 (1907). 

 385 J. J. Sudborough and J. M. Gittins, /. Chem. Soc, 93, 210-217 (1908). 

 38« J. J. Sudborough and M. K. Turner, /. Chem. Soc, 101, 237-240 (1912). 



387 E. R. Thomas and J. J. Sudborough, /. Chem. Soc, 101, 317-328 (1912). 



388 H. Goldschmidt and O. Udby, Z. physik. Chem., 60, 728-755 (1907). 



389 H. Goldschmidt and A. Thuesen, Z. physik. Chem., 81, 30-67 (1912). 



390 C^ N. Hinshelwood and A. R. Legard, J. Chem. Soc, 1935, 587-596. 



39' A. T. Williamson and C. N. Hinshelwood, Trans. Faraday Soc, SO, 1145-1149 

 (1934). 



392 R. A. Fairclough and C. N. Hinshelwood, .7. Chem. Soc, 1939, 593-600. 



393 X. .Menschutkin, Ann., 195, 334-364 (1879). 

 39' N. Menschutkin, Ann., 197, 193-225 (1879). 



398 N. Menschutkin, Ann. chim. phys. [5], 20, 289-361 (1880). 



396 N. Menschutkin, Ann. chim. phys. [5], 23, 14-85 (1881). 



397 N. Menschutkin, Ann. chim. phys. [5], 30, 81-144 (1883). 



