Question

Which of the following compound(s) give $N_2$ on heating?

• A. $N{H}_{4}N{O}_2$
• B. $N{H}_{4}N{O}_3$
• C. $Na{N}_3$
• D. Both (A) and (C)

Answer 1

Answer: (D)

Dinitrogen is a colourless, tasteless, odourless gas and it can be formed by the decomposition of the nitrogenous compounds like nitrates, nitrites, and azides.
Decomposition of the ammonium nitrite gives the dinitrogen and water. This is one of the laboratory preparation of the dinitrogen.
(1) $N{H}_{4}N{O}_2\stackrel{\Delta }{\to }{N}_2+2H_{2}O$
Thermal decomposition of the ammonium nitrate gives the nitrous oxide gas. It is also known as the laughing gas.
(2) $N{H}_{4}N{O}_3\stackrel{\Delta }{\to }{N}_{2}O+2H_{2}O$
Thermal decomposition of the sodium azide gives the dinitrogen gas and sodium metal. This heating should be the absence of oxygen. This method is one of the laboratory preparation of the dinitrogen.
(3) $2Na{N}_3\stackrel{\Delta }{\to }3N_2+2Na$
Hence, Only ammonium nitrite and sodium azide will be able to produce dinitrogen gas on thermal heating.