College chemistry 1

Question

Give the net ionic equation for the reaction (if any) that occurs when aqueous solutions of Rb2S and Ni(NO3)3 are mixed.

Answer 1

(1) Write the complete molecular equation including phases:

Rb₂S(aq) + Ni(NO₃)₂(aq) ==> 2RbNO₃(aq)+ NiS(s)

(2) Dissociate those species than can dissociate to get total ionic equation (aqueous and strong electrolytes):

2Rb⁺(aq) + S^2-(aq) + Ni²⁺(aq) + 2NO₃^-(aq) ==>2Rb⁺(aq) + 2NO₃^-(aq) + NiS(s)

(3) Remove (cancel) spectator ions from each side and keep what's left to get net ionic equation:

Ni²⁺(aq) + S^2-(aq) ==> NiS(s)