In the shorthand notation for galvanic cells, which side corresponds to the anode?

• A. Left
• B. Right
• C. Top
• D. Bottom

Answer: (A)

The main idea is that the anode is the electrode where oxidation occurs, and in the common shorthand notation for galvanic cells the left-hand side is the anode. Oxidation produces electrons that flow through the external circuit to the right-hand side, where reduction occurs. So the left side represents the electrode being oxidized, i.e., the anode, and the right side represents the electrode where reduction happens, i.e., the cathode. For example, in Zn(s) | Zn2+ (aq) || Cu2+ (aq) | Cu(s), zinc is oxidized at the left (anode) to Zn2+, releasing electrons that travel to the right where Cu2+ is reduced to Cu. This left-to-right convention is a standard way to depict spontaneous galvanic cells.