Problem: Which of the following ions will always be a spectator ion in a precipitation reaction?Cl-

We are asked if Cl^- will always be a spectator ion in a precipitation reaction

Solubility Rules:

•Soluble Ionic Compounds:

▪ Group 1A ions (Li⁺, Na⁺, K⁺, etc.) and Ammonium ion (NH₄⁺) are soluble
▪ Nitrates (NO₃^-), Acetates (CH₃COO^- or C₂H₃O₂^-), and most Perchlorates (ClO₄^-) are soluble
▪ Cl^-, Br^-, and I^- are soluble except when paired with Ag⁺, Pb²⁺, Cu⁺, Hg₂²⁺
▪ Sulfates (SO₄^2-) are soluble except those of Ca²⁺, Sr²⁺, Ba²⁺, Ag⁺, and Pb²⁺

•Insoluble Ionic Compounds:

▪ Hydroxides (OH^-) and Sulfides (S^2-) are insoluble except when with Group 1A ions (Li⁺, Na⁺, K⁺, etc.) and ammonium ion (NH₄⁺) and Ca²⁺, Sr²⁺, Ba²⁺
▪ Carbonates (CO₃^2-) and Phosphates (PO₄^3-) are insoluble except when with Group 1A ions (Li⁺, Na⁺, K⁺, etc.) and ammonium ion (NH₄⁺)