In the following reaction sequence, metal (A)+N2Δ⟶(B)−H2O⟶(C)+(D) white ppt (C) is formed and gas (D) is evolved. White ppt (C) dissolves in NaOH solution, while gas (D) gives white fumes in HCl Metal A is
In the following reaction sequence, metal (A)+N2Δ⟶(B)−H2O⟶(C)+(D) white ppt (C) is formed and gas (D) is evolved. White ppt (C) dissolves in NaOH solution, while gas (D) gives white fumes in HCl Metal A is
The correct option is B Al
A is a metal that reacts with nitrogen under heat. Straightaway, we can recall that, among the alkali metals, Li forms a nitride. Also, Be,Mg,Ca,Sr,Ba all form nitrides. Further, Al also forms a nitride. From the given options, we only need to look at Li or Al. Lithium can be ruled out considering the subsequent steps.
As per the question, the metal nitride undergoes hydrolysis which yields a white precipitate and a gas. The gas should most likely be ammonia. Lithium nitride undergoes violent hydrolysis to yield the corresponding hydroxide and ammonia.
Li3N+3H2O⟶3LiOH(aq)+NH3↑
Clearly, lithium hydroxide is solvated/hydrated so it cannot be a precipitate. LiOH is a white hygroscopic crystalline material. It is soluble in water and slightly soluble in ethanol, and is available commercially in anhydrous form and as the monohydrate LiOH.H2O, both of which are strong bases. It is the weakest base among the alkali metal hydroxides. So the answer has to be aluminum and it makes sense because Al(OH)3 is a precipitate. It is amphoteric and dissolves in a basic hydroxide like NaOH
2Al(A)+N2→2AlN(B)AlN+3H2O→Al(OH)3(C)+NH3(D)
Al
A is a metal that reacts with nitrogen under heat. Straightaway, we can recall that, among the alkali metals, Li forms a nitride. Also, Be,Mg,Ca,Sr,Ba all form nitrides. Further, Al also forms a nitride. From the given options, we only need to look at Li or Al. Lithium can be ruled out considering the subsequent steps.
As per the question, the metal nitride undergoes hydrolysis which yields a white precipitate and a gas. The gas should most likely be ammonia. Lithium nitride undergoes violent hydrolysis to yield the corresponding hydroxide and ammonia.
Li3N+3H2O⟶3LiOH(aq)+NH3↑
Clearly, lithium hydroxide is solvated/hydrated so it cannot be a precipitate. LiOH is a white hygroscopic crystalline material. It is soluble in water and slightly soluble in ethanol, and is available commercially in anhydrous form and as the monohydrate LiOH.H2O, both of which are strong bases. It is the weakest base among the alkali metal hydroxides. So the answer has to be aluminum and it makes sense because Al(OH)3 is a precipitate. It is amphoteric and dissolves in a basic hydroxide like NaOH
2Al(A)+N2→2AlN(B)AlN+3H2O→Al(OH)3(C)+NH3(D)
