Question

A series of chemicals were added to some AgNO3(aq). NaCl(aq) was added first to the silver nitrate solution to produce a precipitate. NH3(aq) was then added to produce a clear solution. HNO3(aq) was added last to result in a precipitate. Write a balanced net ionic equation for each of the three steps.

Answer 1

Answer:

First, precipitate of AgCl is formed. Second, a soluble complex of silver and ammonia is formed. Third, AgCl is reproduced due to disappearance of ammonia complex in presence of $HNO_{3}$.

Explanation:

In presence of NaCl, $AgNO_{3}$ forms an insoluble precipitate of AgCl.

Reaction: $Ag^{+}(aq.)+Cl^{-}(aq.)\rightarrow AgCl(s)$

In presence of $NH_{3}$, AgCl gets dissolved into solution due to formation of soluble $[Ag(NH_{3})_{2}]^{+}$ complex.

Reaction: $AgCl(s)+2NH_{3}(aq.)\rightarrow [Ag(NH_{3})_{2}]^{+}(aq.)+ Cl^{-}(aq.)$

In presence of $HNO_{3}$, $[Ag(NH_{3})_{2}]^{+}$ complex gets destroyed and free $Cl^{-}$ again reacts with free $Ag^{+}$ to produce insoluble AgCl

Reaction: $[Ag(NH_{3})_{2}]^{+}(aq.)+2H^{+}(aq.)+Cl^{-}(aq.)\rightarrow AgCl(s)+2NH_{4}^{+}(aq.)$