For the reaction given below identify the anode and

Question

For the reaction given below, identify the anode and describe what happens to the electrode as the reaction continues.

3Fe(s) + Cr₂O₇^2-(aq) + 14 H⁺(aq) → 3Fe²⁺(aq) + 2 Cr⁺³(aq) + 7H₂O(l)

• Fe, converted to Fe²⁺; electrode gains mass.
• Fe electrode at which Cr⁺³ is oxidized; electrode is unchanged.
• Passive electrode at which Cr₂O₇^2-(aq) is oxidized; electrode is unchanged.
• Fe electrode; no change.
• Fe, converted to Fe²⁺; electrode decreases in size.