pBlock ElementsII 1 Question 18
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18. Extra pure $\mathrm{N}_{2}$ can be obtained by heating
======= ####18. Extra pure $\mathrm{N}_{2}$ can be obtained by heating
3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed (a) $\mathrm{NH}_{3}$ with $\mathrm{CuO}$
(b) $\mathrm{NH}{4} \mathrm{NO}{3}$
(c) $\left(\mathrm{NH}{4}\right){2} \mathrm{Cr}{2} \mathrm{O}{7}$
(d) $\mathrm{Ba}\left(\mathrm{N}{3}\right){2}$
(2011)
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Solution:
- $\mathrm{Ba}\left(\mathrm{N}{3}\right){2} \xrightarrow{\text { Heat }} \mathrm{Ba}(s)+3 \mathrm{~N}_{2}(g)$
Azide salt of barium can be obtained in purest form as well as the decomposition product contain solid $\mathrm{Ba}$ as by product alongwith gaseous nitrogen, hence no additional step of separation is required.
Other reactions are
$$ \begin{gathered} \mathrm{NH}{4} \mathrm{NO}{3} \xrightarrow{\text { Heat }} \mathrm{N}{2} \mathrm{O}+2 \mathrm{H}{2} \mathrm{O} \ 2 \mathrm{NH}{3}+3 \mathrm{CuO} \xrightarrow{\text { Heat }} 3 \mathrm{Cu}+3 \mathrm{H}{2} \mathrm{O}+\mathrm{N}{2} \ \left(\mathrm{NH}{4}\right){2} \mathrm{Cr}{2} \mathrm{O}{7} \stackrel{\text { Heat }}{\longrightarrow} \mathrm{Cr}{2} \mathrm{O}{3}+4 \mathrm{H}{2} \mathrm{O}+\mathrm{N}_{2} \end{gathered} $$
