Question

Among the following compounds, the one which does not produce nitrogen gas upon heating is?
A) ${\left( {N{H_4}} \right)_2}C{r_2}{O_7}$
B) $Na{N_3}$
C) $N{H_4}N{O_2}$
D) ${\left( {N{H_4}} \right)_2}\left( {{C_2}{O_4}} \right)$

Answer 1

To solve this question, it is required to have knowledge about the types of bonding present in a compound. Compounds in which nitrogen is bonded with a chelating ligand will have difficulty in breaking its bonds and evolving nitrogen gas on heating.

Complete step by step answer:
Let us see what are the following products formed when we heat the compounds provided in the option to us:
First, let us see the effect of heat on ammonium dichromate:
Let us see the reaction:
${\left( {N{H_4}} \right)_2}C{r_2}{O_7}\xrightarrow{\Delta }{N_2} + C{r_2}{O_3} + 4{H_2}O$
So, from the above reaction, it is clear that the 1 mole of ammonium dichromate decomposes to form 1 mole of nitrogen gas, 1 mole of chromium oxide, and 4 moles of water.
Now let us see the effect of heat on sodium azide:
Let us see the reaction:
$2Na{N_3}\xrightarrow{\Delta }2Na + 3{N_2}$
So, from the above reaction, it is clear that 2 moles of sodium azide decompose to form 2 mole of sodium metal and 3 moles of nitrogen gas.
Now let us see the effect of heat on ammonium nitrate:
Let us see the reaction:
$N{H_4}N{O_2}\xrightarrow{\Delta }{N_2} + 2{H_2}O$
So, from the above reaction, it is clear that 1 mole of ammonium nitrate decomposes to form 1 mole of nitrogen gas and 2 moles of water.
Now let us see the effect of heat on ammonium oxalate:
Let us see the reaction:
${\left( {N{H_4}} \right)_2}\left( {{C_2}{O_4}} \right)\xrightarrow{\Delta }{\left( {CONH} \right)_2} + 2{H_2}O$
So, from the above reaction, it is clear that 1 mole of ammonium oxalate decomposes to form 1 mole of ox-amide and 2 moles of water.
Hence, we can say that ammonium oxalate does not give nitrogen gas on heating.

Therefore, we can conclude that the correct answer to this question is option D.

Note:
In this type of question we must know the decomposition reaction of ammonium dichromate, sodium azide, ammonium nitrate, and ammonium oxalate then only we can find which of the following options does not give nitrogen on heating.