Answer:
2Ag⁺(aq) + S⁻²(aq) → Ag₂S(s)
Step-by-step explanation:
In order to write the net ionic equation we must know if the reactants make a precipitate
In this case the S⁻² (sulfur) bonds to the Ag⁺ to form the correspond precipitate. The other product is the potassium nitrate.
We dissociate both salts:
AgNO₃ → Ag⁺ + NO₃⁻
K₂S → 2K⁺ + S⁻²
Molecular reaction is: 2AgNO₃(aq) + K₂(aq) → Ag₂(s)↓ + 2KNO₃(aq)
The ions are in aqueous solution so we write the phases:
2Ag⁺(aq) + NO₃⁻(aq) + 2K⁺(aq) + S⁻²(aq) → Ag₂S(s) + NO₃⁻(aq) + 2K⁺(aq)
We cancel the ions that are repeat because they are spectators, therefore the net ionic equation is:
2Ag⁺(aq) + S⁻²(aq) → Ag₂S(s)