Question

(a) What are fertilizers.

(b) Give equations for the preparation of two different nitrogenous fertilizers.

Answer 1

Part 1: Fertilizers

Fertilizers are nutrient-rich chemical substances that are added to the soil to increase its fertility of the soil. Due to an increase in fertility of the soil, there is a better yield of food crops when the fertilizers are added in the required amount to the soil.

Part 2: Preparation of two different nitrogenous fertilizers

• Anhydrous ammonia is one of the most common nitrogenous fertilizers used, anhydrous fertilizer is made by adding a catalyst such as ferric oxide and an exact amount of air to the hydrogen gas to provide one nitrogen atom for every three hydrogen atoms.
• The gas mixture is then subjected to very high pressure to produce ammonia.

$\underset{}{\underset{\mathrm{Hydrogen}}{3{\mathrm{H}}_2\left(\mathrm{g}\right)}}+\underset{}{\underset{\mathrm{Nitrogen}}{{\mathrm{N}}_2\left(\mathrm{g}\right)}}\to \underset{}{\underset{\mathrm{Ammonia}}{2{\mathrm{NH}}_3\left(\mathrm{g}\right)}}$

• Urea ammonium nitrate(UAN) is another example of nitrogenous fertilizer it is produced when a heated solution containing dissolved urea is mixed with a heated solution of ammonium nitrate to make a clear liquid fertilizer.
• Approximately 35% urea blended with 45% of ammonium nitrate makes a solution that is 32% nitrogen by weight.

$\underset{}{\underset{\mathrm{Urea}}{\left[\mathrm{CO}{\left({\mathrm{NH}}_2\right)}_2\right]}}+\underset{}{\underset{\mathrm{Ammonium}\mathrm{nitrate}}{\left[{\mathrm{NH}}_4{\mathrm{NO}}_3\right]}}\to \underset{}{\underset{\mathrm{Urea}\mathrm{ammonium}\mathrm{nitrate}}{{\mathrm{CH}}_6{\mathrm{N}}_4{\mathrm{O}}_4}}$