In an electrolytic cell, which of the following is the half-cell where reduction takes place?

In an electrolytic cell, which of the following is the half-cell where reduction takes place?

• A. Anode
• B. Cathode
• C. Combination electrode
• D. Electrode response

Answer: (B)

The main idea is that reduction always occurs at the cathode—the electrode that gains electrons. In an electrolytic cell, an external power source drives the reaction, pushing electrons into the cathode so species in solution are reduced. The anode, by contrast, is where oxidation happens, electrons are drawn away, and it’s connected to the positive terminal of the power source. Other terms shown aren’t standard descriptors of a half-cell, so they don’t describe where reduction occurs.

The main idea is that reduction always occurs at the cathode—the electrode that gains electrons. In an electrolytic cell, an external power source drives the reaction, pushing electrons into the cathode so species in solution are reduced. The anode, by contrast, is where oxidation happens, electrons are drawn away, and it’s connected to the positive terminal of the power source. Other terms shown aren’t standard descriptors of a half-cell, so they don’t describe where reduction occurs.