MR. V. H. VELEY ON THE CONDITIONS OF THE 



In other series of experiments results precisely similar were obtained. 

 A mixture was made up of 202 c.c. sulphuric acid, 73 c.c. water, and 75 c.c. of 

 solution of sodium formate containing 10 grams of the salt. Temperature 64'4-64 0< G. 



The observations in Series II. are in accordance with the preceding series, indicating 

 a temporary increase in rate followed by a period of retardation caused by reducing the 

 pressure. This is doubtless caused by the pumping out of some small quantity of gas 

 stored within the liquid, while the retardation followed by a period of acceleration in 

 Series I. is conversely in part due to some increase of storage within the liquid. The 

 carbonic oxide at the moment of its production from the formic and sulphuric acid is 

 somehow or another more soluble in sulphuric acid than ready-formed carbonic oxide, 

 which is practically insoluble. 



Decomposition of Potassium Chlorate into the Perchlorate and Oxygen. 



A comparative experiment was also made to study the effect of the reduction of 

 pressure on the evolution of oxygen from potassium chlorate, as presenting an example 

 of a fused salt. Into two pieces of combustion tubing were placed 15 grams 

 re-crystallised potassium chlorate ; their ends were subsequently drawn out, the one 

 into a capillary, the other so as to form a convenient joint with the SPRENGEL pump. 

 The two tubes were placed side by side in a small iron pot, filled with molten 

 potassium nitrate, heated by a BUNSEN burner. It was found possible to keep the 

 temperature of the molten nitrate fairly uniform. At first the rate was compared of 

 evolution of oxygen from both tubes, that from one passing directly into the collecting 

 tube, that from the other journeying by way of the SPRENGEL pump. As the rates 

 were equal, the pressure on one was reduced to 20 mm. 



