A Solution Contains 0

question 60

Multiple Choice

A solution contains 0.036 mol L^-1 Cu²⁺ and 0.044 mol L^-1 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 mol L^-1, FeS
• B) 3.6 × 10^-35 mol L^-1, CuS
• C) 3.6 × 10^-35 mol L^-1, FeS
• D) 1.4 × 10^-16 mol L^-1, CuS
• E) 1.4 × 10^-16 mol L^-1, both CuS and FeS will precipitate

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Definitions:

Mean

The average of a set of numbers, calculated by dividing the sum of all the values in the set by the number of values.

Binomial Distribution

A probability distribution that represents the number of successes in a fixed number of independent Bernoulli trials, each with the same probability of success.

Binomial Table

A mathematical table used to determine the probability of obtaining various numbers of successes in a fixed number of trials in a binomial experiment.

Cumulative Probability

This term refers to the probability that a random variable is less than or equal to a specified value.