Question

In Duma's method, the gas which is collected in nitrometer is

(a) N₂

(b) NO 

(c) NH₃ 

(d) H₂

Answer 1

Correct option is (a) N₂

In addition to carbon dioxide and water, free nitrogen is produced when a nitrogen organic molecule is burned with too much copper oxide in an environment of carbon dioxide. 

Chemical processes include: 

C + 2CuO → CO₂ + 2Cu₂H + CuO → H₂O + Cu

Similarly,

Nitrogen + CuO → N₂ + Oxides of nitrogen, thus nitrometer will contain nitrogen.

Oxides of nitrogen + Cu → N₂ + CuO

The mixture of gases is collected over KOH solution that absorbs CO₂​.