Cathode

Definition

The cathode is the electrode where reduction occurs in an electrochemical cell. It is the positive terminal in a galvanic cell.

5 Must Know Facts For Your Next Test

1. In a galvanic cell, the cathode is the site of reduction reactions.
2. Electrons flow toward the cathode from the anode.
3. The cathode is typically marked as the positive terminal in a galvanic cell.
4. Reduction at the cathode means that a species gains electrons.
5. Common examples of reduction reactions at the cathode include $\text{Cu}^{2+} + 2e^{-} \rightarrow \text{Cu}$ and $\text{Ag}^{+} + e^{-} \rightarrow \text{Ag}$.

Review Questions

• What type of reaction occurs at the cathode in a galvanic cell?
• In which direction do electrons flow relative to the cathode?
• How is the terminal of a cathode typically marked in a galvanic cell?

Related terms

Anode:

The electrode where oxidation occurs; it is the negative terminal in a galvanic cell.

Reduction:

A chemical reaction that involves gaining electrons.

Electrolyte:

A substance containing free ions that make it electrically conductive, used to allow ion flow between electrodes.