What mass of chromium could be deposited by electrolysis of an aqueous solution of Cr₂(SO₄)₃ for 160 min using a constant current of 15.0 A? Assume 100% current efficiency.(F = 96485 C/mol) A) 0.431 g B) 25.9 g C) 232.8 g D) 0.187 g E) 38.8 g

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The charge passed is calculated using Q = I × t = 15.0 A × 160 min × 60 s/min = 144000 C. The moles of electrons are Q/F = 144000 C / 96485 C/mol = 1.492 mol. The reaction is Cr^3+ + 3e^- → Cr, so 1.492 mol of electrons deposit 1.492/3 = 0.497 mol of Cr. The mass of Cr is 0.497 mol × 51.996 g/mol = 25.9 g.

What Mass of Chromium Could Be Deposited by Electrolysis of an Aqueous