Calculate the Minimum Concentration of Cr³⁺ That Must Be Added

question 56

Multiple Choice

Calculate the minimum concentration of Cr³⁺ that must be added to 0.095 M NaF in order to initiate a precipitate of chromium(III) fluoride.[K_sp(CrF₃) = 6.6 × 10^-11]

• A)0.023 M
• B)0.032 M
• C)7.7 × 10^-8 M
• D)2.9 × 10^-9 M
• E)6.9 × 10^-10 M

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Definitions:

First Instinct Fallacy

The misconception that an individual's initial answer or gut reaction is always the correct choice, especially in the context of test-taking or decision-making.

Ironic Processing

A psychological process where attempts to suppress certain thoughts make them more likely to surface.

Counterfactual Thinking

The mental process of imagining alternative scenarios and outcomes that could have happened, but didn't.

False Consensus Effect

The tendency to overestimate how much other people share our beliefs, attitudes, and behaviors.