Balance and write the net ionic equation for the precipitation reaction below

Question

K2S+Ni(No3)_KNo3+NiS

Answer 1

I have corrected and balanced the molecular equation as follows:
K2S(aq) + Ni(NO3)2(aq) ==> 2KNO3(aq) + NiS(s)
S^2-(aq) + Ni^2+(aq) ==> NiS(s)

Answer 2

What is the role