Question

How is nitrogen prepared in the laboratory? Write the chemical equations of the reactions involved.

Answer 1

We know that nitrogen is a chemical element and nitrogen compounds are nitric acid, ammonia, etc. are used as important compounds in industries. It is a nonmetallic element because of its high electronegativity and usual gaseous form and also nitrogen has a lack of solid form. At STP (standard temperature and pressure) two nitrogen atoms combine to form dinitrogen, an odorless gas.

Complete answer:
We must have to know that in the laboratory method of preparation nitrogen is prepared by the reaction of ammonium chloride with sodium nitrate. This is heated and small amounts of water are added to this reaction. The product is ammonium nitrate and sodium chloride. This reaction is a double decomposition. Nitrogen is prepared in the laboratory by heating an equimolar aqueous solution of ammonium chloride and sodium nitrite. The ammonium nitrite formed as a result of double decomposition reaction, decomposes to form dinitrogen.
$N{{H}_{4}}C{{l}_{\left( aq \right)}}+NaN{{O}_{2(aq)}}\to N{{H}_{4}}N{{O}_{2}}_{\left( aq \right)}+NaC{{l}_{\left( aq \right)}}$
$\underset{Ammonium\text{ }nitrate\text{ }}{\mathop{N{{H}_{4}}N{{O}_{2\left( aq \right)}}}}\,\xrightarrow{\Delta }\underset{Nitrogen}{\mathop{{{N}_{2\left( g \right)}}}}\,+2{{H}_{2}}{{O}_{\left( l \right)}}.$

Additional Information:
Nitrogen is almost non-reactive at ordinary temperatures. It neither burns nor supports combustion. The chemical inertness of ${{N}_{2}}$ at ordinary temperatures is due to the high stability of the molecule. In a molecule of ${{N}_{2}}$ , the two nitrogen atoms are linked together by a triple bond. The triple bond has a very high bond enthalpy(amount of heat energy required to break a chemical bond) . Due to very high bond dissociation enthalpy ${{N}_{2}}$ is almost unreactive towards most of the reagents.

Note:
Remember that ammonium nitrate is not an explosive on its own but it is oxidized when oxygen is in its surroundings and this creates a violent explosion and generates heat, nitrogen oxides also. When Ammonium nitrate is stable at STP. It is an important fertilizer. Ammonium nitrate is not a health hazardous substance.