Answer:
2Li⁺(aq) + S²⁻(aq) + Cu²⁺(aq) + 2NO₃⁻(aq) ⟶ 2Li⁺(aq) + 2NO₃⁻(aq) + CuS(s)
Explanation:
An ionic equation uses the symbols (aq) [aqueous] to indicate ions that are soluble in water and (s) [solid] to indicate insoluble solids.
In this equation, aqueous lithium sulfide might react with aqueous copper(II) nitrate to form lithium nitrate and copper(II) sulfide.
1. Possible molecular equation
Li₂S(aq) + Cu(NO₃)₂(aq) ⟶ 2LiNO₃ + CuS
2. Ionic equation
Nitrates and the salts of Group 1 metals are soluble, so LiNO₃ is soluble.
Sulfides are usually insoluble, so CuS is a precipitate.
We write the formulas of soluble salts as ions, and those of insoluble salts in the "molecular" form.
The complete ionic equation is
2Li⁺(aq) + S²⁻(aq) + Cu²⁺(aq) + 2NO₃⁻(aq) ⟶ 2Li⁺(aq) + 2NO₃⁻(aq) + CuS(s)