When a Solution of Cu(II) Chloride, CuCl₂ , Is Added

question 104

Multiple Choice

When a solution of Cu(II) chloride, CuCl₂ , is added to a solution of potassium sulfide, K₂S, a black precipitate of copper sulfide, CuS, forms. Which of the following is the total ionic equation for this reaction?

• A) CuCl₂(aq) + K₂S(aq) → CuS(s) + 2 KCl(aq)
• B) Cu²⁺(aq) + Cl₂^2-(aq) + K₂²⁺(aq) + S^2-(aq) → CuS(s) + K₂²⁺(aq) + Cl₂^2-(aq)
• C) Cu²⁺(aq) + 2 Cl^-(aq) + 2 K⁺(aq) + S^2-(aq) → CuS(s) + 2 K⁺(aq) + 2 Cl^- (aq)
• D) Cu²⁺(aq) + S^2-(aq) → CuS(s)

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