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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Definitions:

Sample Number

The count of individual units selected from a population to represent the whole, used in statistical analysis to draw conclusions about the larger group.

Convenience Sampling

A non-probability sampling method where participants are selected based on their easy availability and proximity to the researcher, which may limit the generalizability of the findings.

Pretesting

A method used to test or evaluate materials or interventions before their final application or implementation.

Population

The entire group of individuals or instances about whom the study is focused, from which a sample may be drawn for analysis.