A Solution Contains 0

question 84

Multiple Choice

A solution contains 0.036 M Cu²⁺ and 0.044 M Fe²⁺.A solution containing sulfide ions is added to selectively precipitate one of the metal ions from solution.At what concentration of sulfide ion will a precipitate begin to form? What is the identity of the precipitate? K_sp(CuS) = 1.3 × 10^-36,K_sp(FeS) = 6.3 × 10^-18.

• A) 1.4 × 10^-16 M, FeS
• B) 3.6 × 10^-35 M, CuS
• C) 3.6 × 10^-35 M, FeS
• D) 1.4 × 10^-16 M, CuS
• E) No precipitate will form at any concentration of sulfide ion.

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