Question

Which of the following compounds can be used to obtain free nitrogen?

• A. $N{H}_{4}N{O}_2$
• B. $HN{O}_2$
• C. $HN{O}_3$
• D. $N{H}_3$

Answer 1

The correct option is A $N{H}_{4}N{O}_2$

$N{H}_{4}N{O}_2$, ammonium nitrite is the only convenient compound that can be used to obtain free nitrogen, even in laboratories.
$N{H}_{4}Cl\left(aq\right)+NaN{O}_2\left(aq\right)\to N{H}_{4}N{O}_2\left(aq\right)+NaCl\left(aq\right)$
By heating ammonium nitrite ​
$N{H}_{4}N{O}_2\left(aq\right)\stackrel{\Delta }{\to }{N}_2\left(g\right)\uparrow +2H_{2}O\left(l\right)$