For a galvanic cell that uses the following two half-reactions, Cr₂O₇^2-(aq) + 14 H⁺(aq) + 6 e^- → 2 Cr³⁺(aq) + 7 H₂O(l)
Pb(s) → Pb²⁺(aq) + 2 e^-
How many moles of Pb(s) are oxidized by one mole of Cr₂O₇^2-?

Question

Quizplus · Accepted Answer

One mole of Cr2O7^2- requires 6 electrons for reduction. Since each Pb atom provides 2 electrons when oxidized, 3 moles of Pb are needed to provide the 6 electrons.

For a Galvanic Cell That Uses the Following Two Half-Reactions