AP Chemistrymediummcq1 pt
What total charge, in coulombs, is required to deposit 0.0500 mol of Cr metal from a Cr³⁺ solution? (F = 96,485 C/mol)
A.14,500 C
B.4,820 C
C.28,900 C
D.145,000 C
Explanation
Core Concept
Chromium(III) needs three electrons per atom: Cr³⁺ + 3 e⁻ → Cr. Depositing 0.0500 mol Cr therefore consumes 3 × 0.0500 = 0.150 mol of electrons. Charge equals electron moles times the Faraday constant: 0.150 mol × 96,485 C/mol ≈ 1.45 × 10⁴ C ≈ 14,500 C. Faraday's law always converts product amount to electron moles before any charge calculation.
Correct Answer
A14,500 C
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