A current deposits copper from copper(II) sulfate solution: . How many moles of electrons are needed to deposit mol of copper?
Answer and explanation
Correct answer: C. mol
- Step 1: Each ion needs electrons.
- Step 2: Moles of electrons mol.
Answer
mol.
Why not the others: mol: assumes one electron per copper ion. mol: halves the moles of copper instead of doubling. mol: uses four electrons per copper ion.
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