## Chemistry and Chemical Reactivity (9th Edition)

(a) 1. Write the $K_{sp}$ expression: $NiCO_3(s) \lt -- \gt 1Ni^{2+}(aq) + 1CO_3^{2-}(aq)$ $K_{sp} = [Ni^{2+}]^ 1[CO_3^{2-}]^ 1$ 2. Find the $Q_{sp}$ value $Q_{sp} = (2.4 \times 10^{-3})^ 1 \times (1.0 \times 10^{-6})^ 1$ $Q_{sp} = 2.4 \times 10^{-9}$ $K_{sp} (NiCO_3) = 1.4 \times 10^{-7}$ Since $Q_{sp} \lt K_{sp}$, there will be no precipitation ----- (b) 1. Write the $K_{sp}$ expression: $NiCO_3(s) \lt -- \gt 1Ni^{2+}(aq) + 1CO_3^{2-}(aq)$ $K_{sp} = [Ni^{2+}]^ 1[CO_3^{2-}]^ 1$ 2. Find the $Q_{sp}$ value $Q_{sp} = (2.4 \times 10^{-3})^ 1 \times (1.0 \times 10^{-4})^ 1$ $Q_{sp} = 2.4 \times 10^{-7}$ $K_{sp} (NiCO_3) = 1.4 \times 10^{-7}$ Since $Q_{sp} \gt K_{sp}$, there will be precipitation