Write a balanced net ionic equation for each reaction of (NH4)2S(aq) + Co(NO3)2(aq) -> CoS(s) + NH4NO3(aq)

Amixture initially contains a, b, and c in the following concentrations: [a] = 0.300 m , [b] = 1.05 m , and [c] = 0.550 m . the following reaction occurs and equilibrium is established: a+2b⇌c at equilibrium, [a] = 0.140 m and [c] = 0.710 m . calculate the value of the equilibrium constant, kc.