1. **State the problem:** We need to find the volume of 0.205 M K3PO4 solution required to completely react with 114 mL of 0.0116 M NiCl2. 2. **Write the balanced chemical equation:** $$2 \text{K}_3\text{PO}_4(aq) + 3 \text{NiCl}_2(aq) \rightarrow \text{Ni}_3(\text{PO}_4)_2(s) + 6 \text{KCl}(aq)$$ 3. **Identify the molar relationship:** From the equation, 2 moles of K3PO4 react with 3 moles of NiCl2. 4. **Calculate moles of NiCl2:** $$\text{moles NiCl}_2 = M \times V = 0.0116 \times 0.114 = 0.0013224$$ 5. **Use mole ratio to find moles of K3PO4 needed:** $$\text{moles K}_3\text{PO}_4 = \frac{2}{3} \times 0.0013224 = 0.0008816$$ 6. **Calculate volume of K3PO4 solution:** $$V = \frac{\text{moles}}{M} = \frac{0.0008816}{0.205}$$ 7. **Show cancellation step:** $$V = \frac{\cancel{0.0008816}}{\cancel{0.205}} = 0.0043 \text{ L}$$ 8. **Final answer:** The volume of K3PO4 solution required is **0.00430 L** (to three significant figures).