206f 



jBxplodes with 

 oxigen. 



Sums teautU 

 fully in oxigen 

 gas. 



Compofedofme- 

 tallic arfenic and 

 ^idrogen. 



ARSENIATED HIDROGEN GaS. 



If two parts of arfeniated hidrogen be mingled with tfireii 

 of 6xigen, and a taper be prefented to the mixture^ an ex- 

 plofion lakes place; no metallic arfenic is feparated, but the 

 produfls are arfenious acid and water: foap-bubbles with the 

 mixture of thefe gafes, explode with a bhiiHi white flame, 

 leaving a white fmoke and ftrong alliaceous odour. Equal 

 parts of arfeniated hidrogen and oxigen gafes, fired in like 

 manner, do not explode fo loudly, but the report is accompa- 

 nied with a much more vivid flame/ A ftream of arfeniated 

 hidrogen, iffuing from a bladder fitted with a flop-cock, and 

 fet to burn in a large receiver filled with oxigen, yielded 

 arfenic acid. The combuftion in this manner is uncommonly 

 beautiful ; the gas burns with a blue flame of uncommon 

 fplendor. 



Two parts of arfeniated hidrogen, and one of oxigen gasj* being 

 detonated in a clofe veffel by means of the electric fpark, left 

 a fmall refiduum ; on repeating the experiment, the deto- 

 nating tube broke during the explofion, which prevented the 

 examination of the refidue. From what has been fo far re- 

 lated, it becomes evident that the conftituent parts of arfe- 

 niated hidrogen gas, are me'iallic arfenic and hidrogen. Were 

 it poffible to determine with abfolute certainty, thai no in- 

 creafe of volume took place during the folution of arfenic in 

 hidrogen, the proportion of the conftituent parts of this gas 

 might be afcertained thus : 



French weight and 

 meafure* 

 One cubic inch of hidrogen, weighs - 0^0353 

 One cubic inch of arfeniated hidrogen, weighs 0,2435 



Deducling the former from the laiier, we get 0,2082 

 Which is the quantity of arfenic difToived in the gas, confer 

 quentiy one cubic inch of arfeniated hidrogen gas, confifts of 

 0,0363 hidrogen, and 0,2082 arfenic ; and one cubic inch of 

 Ihls gas contains about | grain of metallic arfenic. 



Habitudes of arfeniated Hidrogen to Acids. 



Its habitudes to Into a phial, containing about eight cubic inches of ar-» ' 

 acids. feniated hidrogen, I poured a half cubic i:)C:. of concentrated 



nj°^"acid. nitric acid. The moment the acid came into contact with the- 



gas 



