Which of the following is the correct net ionic equation for the reaction between aqueous solutions of Na3PO4 and CuSO4?

• A. Cu^{2+}(aq) + SO_4^{2-}(aq) → CuSO_4(s)
• B. Na^+(aq) + SO_4^{2-}(aq) → Na_2SO_4(s)
• C. 2Cu^{2+}(aq) + 2PO_4^{3-}(aq) → Cu_3(PO_4)_2(s)
• D. Na^+(aq) + PO_4^{3-}(aq) → Na_3PO_4(s)

Answer: (C)

Verified step by step guidance

1. Identify the ions present in the aqueous solutions: Na3PO4 dissociates into 3 Na^{+} and PO_4^{3-} ions, and CuSO4 dissociates into Cu^{2+} and SO_4^{2-} ions.
2. Determine which ions will form a precipitate by checking the solubility rules. Phosphate ions (PO_4^{3-}) often form insoluble compounds with transition metal ions like Cu^{2+}, while sulfates (SO_4^{2-}) with Cu^{2+} are generally soluble.
3. Write the balanced molecular equation for the reaction between Cu^{2+} and PO_4^{3-} ions forming the precipitate Cu_3(PO_4)_2, ensuring charge and atom balance.
4. Write the full ionic equation by expressing all strong electrolytes as their constituent ions, except for the precipitate which remains as a solid.
5. Derive the net ionic equation by canceling out the spectator ions (ions that do not participate in the formation of the precipitate), leaving only the ions that form the solid precipitate.