Question

Nitrogen gas is prepared :

• A. By heating ammonium nitrate.
• B. By reacting excess chlorine with liquor ammonia.
• C. By passing HNO3 vapours on red hot copper.
• D. By heating lead nitrate.

Answer 1

Answer: (C)

By passing HNO3 vapours on red hot copper.

Answer 2

(1) (NH4)NO3 gives N2O, (2) chlorine (excess) with liquor NH3 forms NCl3 and (4) Pb(NO3)2 gives NO2 not N2 on heating.

(3) 5Cu (red hot) + 2HNO3 $\longrightarrow$ 5CuO + N2 + H2O