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IOWA ACADEMY OP SCIENCE 
Ca (N03)2 and NH 4 NO 3 . A series of experiments on the amount and rate of 
formation of nitric acid during the reaction in ethyl alcohol showed that the 
nitric acid formed is always a constant percentage (about 70%) of the amount 
of silver nitrate which has reacted, and the amount formed is independent of 
the initial concentration of the reactants. More acid seems to be formed in 
mixtures of alcohol and water than in either pure solvent. The velocity co- 
efficient curves for ethyl and methyl iodide in the aqueous alcoholic mixtures 
show a pronounced maximum near the alcohol end of the curve. 
They offer as a tentative suggestion for the variation in the velocity coeffi- 
cients with change in initial concentrations that “it is the undissociated silver 
nitrate which reacts and that the decrease in the bimolecular velocity coefficients 
which might be expected therefrom is compensated by the accelerating action 
of one of the reacting products.” They were, however, unable to determine 
which of the products is the disturbing factor. 
Donnan and Potts^ made an attempt to determine whether the peculiar be- 
havior already noted is due to the presence of the NO 3 group. They substituted 
silver lactate for silver nitrate in 60% alcohol-water solutions. Two series, 
using different equivalent concentrations of the reactants, were studied. The 
results showed that the disturbing factor in this case is absent. The ratio of 
the lactic acid formed to that of the silver lactate used up was the same as for 
nitric acid and silver nitrate, viz., approximately 70%. 
Since free acid is one of the main products when solvents containing a hy- 
droxyl group are used, they decided to carry out the experiments using ethyl 
iodide and silver nitrate in acetonitrile. No acid, other than a slight trace 
possibly due to impurities, was found. The experimental results resembled 
those obtained when alcohol was used as solvent. The simple bimolecular 
equation holds for all concentrations studied except 0.10 N, but the velocity 
coefficients vary with the initial concentrations of the reacting substances. This 
would show then that the variation is not dependent upon the formation of acid. 
Euler^ studied the reaction between chlor-acetic acid and silver nitrate in water 
and in 45% alcohol-water mixtures. The reaction speed in 0.25 N equivalent 
solutions was decreased 100% in the presence of 0.5N nitric acid. 
Senter^ investigated the reactions between silver nitrate and bromacetic, 
a-bromproplonic, a-brombutyric acids and their sodium salts. Traces of silver 
bromide added to the reacting mixtures were found to increase the initial 
velocity coefficients three to six times. The same was found to be true when 
traces of silver iodide were added to reaction mixtures of methyl iodide and 
silver nitrate in aqueous solutions. In these experiments the addition of nitric 
acid shows considerable retarding effect. Benzenesulphonic acid was found to 
have a still greater retarding effect than nitric. 
Senter suggests the catalytic action of the silver halides as being the possible 
cause of the kinetic disturbances observed in reactions in alcoholic solvents. 
No measurements of the velocity coefficients of the reaction in the mixed 
alcohols have been made and very little done with silver nitrate and ethyl iodide 
in methyl alcohol as solvent. It was thought some interesting facts might be 
brought to light through a systematic study of the reactions of silver nitrate 
ij. Chem. Soc., .97, 1882 (1910). 
iBer. d. chem. Ges., 39. 2726 (1906). 
^J. Chem. Soc., 97, 346 (1910). 
