478 NITROUS OXIDE. 



6. ACTION OF COMBUSTIBLES. 



(a.) JL lighted candle burns, with increased brilliancy in this gas, 

 and with a white flame, which, before extinction, appears edged with 

 blue. 



(b.) Dr. Turner states, that an extinguished candle retaining " a 

 red wick," is lighted again by immersion in this gas.* 



(c.) Sulphur burning with a blue flame, is immediately extinguish- 

 ed; but with a white flame, that is, at a higher temperature, it hums 

 vividly, and the flame becomes rose-colored. 



(d.) Phosphorus may be melted, and if touched with a red hot wire, 

 it may be even sublimed in this gas without burning ; but if touched 

 with a white hot iron the phosphorus burns almost explosively. 



The jar should be strong, not more than one eighth filled with 

 the gas, and the wire well curved, so that it may be expeditiously 

 withdrawn ; not unfrequently the jar bursts in the experiment. The 

 combustion ceases when about one half the gas is consumed, and 

 the product is phosphoric acid, nitrogen being evolved. 



(e.) If the phosphorus be already on fire when it is introduced, it 

 continues to burn but with increased splendor, greater than we should 

 infer from the proportion of oxygen which the gas contains. 



(f.) Charcoal, vividly ignited, is said to burn in this gas more bril- 

 liantly than in common air,f and if properly managed to produce, 

 for each measure of nitrous oxide, one of nitrogen, and half a meas- 

 ure of carbonic oxide, equivalent to half a measure of oxygen.f 



(g.) Hydrogen gas, mingled, volume for volume with this gas, ex- 

 plodes by the contact of flame, and by its acid, the nitrous oxide is 

 decomposed by spongy platinum at the common temperature. 



With 40 hydrogen to 39 nitrous oxide, there remains only nitro- 

 gen, and if the proportion of hydrogen is smaller, some nitric acid 

 is produced. In general, the products of the combustion of hydro- 

 gen in nitrous oxide, are the same as in oxygen, or in common air, 

 and nitrogen remains equal in volume to the original gas. 



(h.) Pyrophorus does not take flre spontaneously in this gas, but 

 it takes fire if touched with an iron strongly heated, but not to igni- 

 tion. It is the only body which burns in this gas, at a temperature 

 below ignition. 



Si.) Phosphuretted hydrogen flashes in this gas. 

 j.) Potassium and sodium decompose it below a red heat, evol- 

 ving nitrogen, and forming alkali. 



* This has never succeeded with me. 



t In this experiment I have never been able to succeed. 



* Henry. Ibid. 



