Heating Ammonium Nitrate to Obtain Oxides of Nitrogen

When ammonium nitrate (NH4NO3) is heated, it decomposes to produce different oxides of nitrogen. The specific oxide of nitrogen obtained depends on the temperature at which the decomposition occurs.

Decomposition of Ammonium Nitrate

Ammonium nitrate decomposes endothermically into nitrous oxide (N2O) and water (H2O) when heated to temperatures around 250°C. The decomposition reaction can be represented as follows:

2NH4NO3(s) → 2N2O(g) + 4H2O(g)

Explanation of the Correct Answer

The correct answer is option (b) Nitrous oxide. When ammonium nitrate is heated to 250°C, it decomposes to produce nitrous oxide (N2O) as one of the products. Nitrous oxide is a colorless and odorless gas commonly known as laughing gas.

Comparison with Other Oxides of Nitrogen

Let's briefly discuss the other options mentioned:

a) Nitric oxide (NO): Nitric oxide is produced when ammonium nitrate is heated to higher temperatures (above 500°C). It is a colorless gas with a pungent odor.

c) Nitrogen dioxide (NO2): Nitrogen dioxide is produced when ammonium nitrate is heated to even higher temperatures (above 800°C). It is a reddish-brown gas with a sharp, suffocating odor.

d) Dinitrogen tetraoxide (N2O4): Dinitrogen tetraoxide is not directly obtained from the decomposition of ammonium nitrate. It is produced when nitrogen dioxide (NO2) is cooled and forms a dimer.

Conclusion

On heating ammonium nitrate at 250°C, nitrous oxide (N2O) is obtained as one of the products. It is important to note that the decomposition of ammonium nitrate can produce different oxides of nitrogen depending on the temperature at which it is heated.