A Mining Operation Needs to Separate Silver and Copper

question 28

Multiple Choice

A mining operation needs to separate silver and copper. You are hired as a summer intern in a beautiful Colorado mining town, and one of your tasks is to determine whether this separation can be accomplished by oxidizing the metals to Ag⁺ and Cu⁺, each one at a concentration of 0.15 M, and then precipitate one as the chloride salt without precipitate the other. AgCl precipitates first. What is the concentration of the Ag⁺ remaining in solution when CuCl begins to precipitate? For AgCl, pK_sp = 9.74. and for CuCl, pK_sp = 6.76.

• A) 1.57  10^-2 M
• B) 1.57  10^-4 M
• C) 2.23  10^-2 M
• D) 2.23  10^-4 M
• E) 3.72  10^-3 M

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Definitions:

Probability Samples

Sampling methods in research that give each member of a population a known chance of being selected, facilitating the generalization of results to the larger population.

Randomization Techniques

Statistical methods used to ensure each participant in an experiment has an equal chance of being assigned to any group, reducing bias.

Representative Sample

A subset of a population that accurately reflects the members of the entire population, used in statistical analysis or research studies.

Sampling Frame

A list or database from which a sample is drawn for a study, representing the entire population of interest.