Page:Outlines of Physical Chemistry - 1899.djvu/268

 ��OUTLINES OF PHYSICAL CHEMISTEY

��their avidity. The table given below contains the principal results obtained in the saponification of methyl acetate and in the inversion of cane sugar.

The catalysis of the acetate was carried out as described above, but at the temperature 26° and at a different con- centration (10 cubic centimetres of normal acid, 1 cubic centimetre of methyl acetate, and sufficient water to bring the volume up to 15 cubic centimetres). Column I. con- tains the coefficient k for each acid, that is, the constant

1 .log A - a "

��t

��n

��A — a„

��In column II. the coefficients of speed, relative to that of hydrochloric acid taken as unity, are given. Column III. contains the constants k deduced from the rapidity of the inversion of the sugar :

��(k = 1 kg?*--*).

\ t n "n - A/

��and in column IV. these constants are compared with that for hydrochloric acid. The figures of column V. are the relative avidities of the acids, according to Thomsen and Ostwald.

��Acids

�I.

�n.

�m.

�IV.

�V.

�Hydrochloric

�Hydrobromic

�Hydriodic.

� � � �Nitric.

�Chloric

� �Sulphuric.

�Ethylsulphuric.

� �Ethylsulphonic.

� �Benzenesulphonic

� �Formic

�Acetic

�Monochloracetic.

�Dichloracetic

�Trichloracetic

�Oxalic

�. Tartaric

i

�� �