AP Chemistrymediummcq1 pt
Which ions are spectator ions in the reaction between aqueous Na₂CO₃ and aqueous CaCl₂?
A.Na⁺ and Cl⁻
B.Ca²⁺ and CO₃²⁻
C.Na⁺ and CO₃²⁻
D.Ca²⁺ and Cl⁻
Explanation
Core Concept
The precipitate is CaCO₃, so Ca²⁺ and CO₃²⁻ combine. Na⁺ and Cl⁻ stay dissolved and unchanged on both sides — spectator ions that cancel from the net ionic equation.
Correct Answer
ANa⁺ and Cl⁻
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