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XXXIX. Action of Alkaline Solution of Permanganate of 

 Potash on certain Gases. By J. A. Wanklyn and W. J. 



Cooper*. 



IN continuation of our work on the oxidizing-power of 

 strongly alkaline solution of permanganate of potash, we 

 have made experiments on the common gases, and have arrived 

 at results of some interest. The solution which we have em- 

 ployed in these experiments contained 16 grms. of permanga- 

 nate of potash and 5 grms. of caustic potash dissolved in a 

 litre of distilled water. 



Binoxide of Nitrogen, NO. 



This gas was prepared in the usual manner by the action of 

 diluted nitric acid on metallic copper. On submitting it to 

 the above-described solution of alkaline permanganate there 

 was immediate action, the gas being instantly absorbed at 

 ordinary temperatures, and the solution being instantly deco- 

 lorized and caused to deposit the brown hydrated binoxide of 

 manganese. 



110 cubic centims. of NO and 30 cubic centims. of the 

 potash-and-permanganate solution were shaken up together. 

 Immediately the solution lost its colour and deposited the 

 brown binoxide of manganese, and 85 cubic centims. of the 

 gas was absorbed. 



The reaction is 



NO + KMn0 4 = Mn0 2 + KN0 3 . 



Protoxide of Nitrogen, N 2 0. 



This gas, prepared in the usual way from nitrate of ammonia, 

 appears to be quite without action on the alkaline solution of 

 permanganate of potash. Even on prolonged heating of the 

 materials in the water-bath there was no sign whatever of 

 action, the permanganate preserving its brilliancy, and the 

 volume of the enclosed gas undergoing no diminution. 



Nitrogen Gas. 



Experiments published some years ago by one of us show 

 that this gas is not attacked by the alkaline solution of per- 

 manganate, even when the temperature is considerably raised. 



Carbonic Oxide, CO. 



This gas, prepared by the action of excess of sulphuric acid 

 on ferrocyanide of potassium, is attacked by the alkaline solu- 



* Communicated by the Authors. 



