Question

What would you observe in each of the following cases?
Water is added to the product formed, when aluminium is burnt in a jar of nitrogen gas.

Answer 1

Aluminum $\left(\mathrm{Al}\right)$ burnt in a jar of nitrogen gas $\left({\mathrm{N}}_2\right)$:

• When aluminum is burnt in a jar of nitrogen gas, aluminum nitride $\left(\mathrm{AlN}\right)$ is formed.
• $2\mathrm{Al}\left(\mathrm{s}\right)+{\mathrm{N}}_2\left(\mathrm{g}\right)\to 2\mathrm{AlN}\left(\mathrm{s}\right)$

Addition of water to aluminum nitride $\left(\mathrm{AIN}\right)$:

• Aluminum nitride undergo hydrolysis and is decomposed by water to give ammonia gas.
• $\mathrm{AlN}\left(\mathrm{s}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)⟶\mathrm{Al}(\mathrm{OH}{)}_3\left(\mathrm{aq}\right)+{\mathrm{NH}}_3(\mathrm{g})\uparrow$

Therefore, when aluminum is burnt in a jar of nitrogen gas, aluminum nitride is formed which reacts with water to release ammonia gas.