EVOLUTION OF GASES FROM HOMOGENEOUS LIQUIDS. 



It is probable that the factor 1/C is dependent not only upon the temperature, 

 conditions of concentration remaining the same, but also upon the variable and quite 

 unknown condition of the cleanliness of the containing vessel, whereby, in some 

 cases, more nuclei are presented for the evolution of the gas than in others. The 

 method of procedure after the residue had been determined was to siphon off the 

 acid as far as possible, and to keep closed the neck of the decomposition flask with the 

 thermometer-bearing cork between each series of observations ; but probably small 

 particles, not discernible by the eye, may have been introduced, producing a consider- 

 able acceleration in the rate of decomposition. This is rendered evident by the 

 following series of observations, made with a solution of sodium formate containing 

 particles of silica, which led, as mentioned above, to the investigation of the effect of 

 finely divided particles. 



SERIES VL 

 Mixture as in Series I. Temperature 35*9. 



On comparison of the Series VI. with Series I., it is evident that the value for 1/C 

 in both cases is practically equal, viz., '000165 and '000162 ; but in Series I. the 

 reaction was effected at a temperature of 737, and in Series VI. at a temperature 

 of 35 0> 9. But the law governing the rate of this chemical change is still valid in the 

 presence of these finely divided particles, the concordance between the observed and 

 calculated values for T being especially marked in this series. 



It will be necessary to quote only one more series, in which observations were 

 carried on almost to the ultimate limit of the reaction. 



