An aqueous solution of ammonium chloride is treated with sodium nitrite to produce a gas X. When gas X is passed over heated magnesium, it forms a solid compound Y. Upon hydrolysis of compound Y with water, another gas Z is evolved. The gas Z is:

Step-by-step solution

Step 1: Treating an aqueous solution of ammonium chloride with sodium nitrite produces dinitrogen gas (X). NH ₄ Cl(aq) + NaNO ₂ (aq) N ₂ (g) + 2 H ₂ O(l) + NaCl(aq) Thus, gas X is N ₂ . Step 2: Dinitrogen reacts with heated alkaline earth metals like magnesium to form ionic nitrides. Magnesium nitride (Y) is formed. 3 Mg + N ₂ Mg ₃ N ₂ Thus, compound Y is Mg ₃ N ₂ . Step 3: Hydrolysis of metal nitrides yields the corresponding metal hydroxide and ammonia gas (Z). Mg ₃ N ₂ + 6 H ₂ O 3 Mg(OH) ₂ + 2 NH ₃ (g) Thus, the