What occurs at the cathode in an electrochemical cell?

In an electrochemical cell, the cathode is the electrode where reduction occurs. This process involves the gain of electrons by ions or molecules. At the cathode, positively charged ions in the electrolyte move towards the cathode, where they receive electrons from the external circuit, thus reducing them to a neutral state or a lower oxidation state.

This fundamental principle is rooted in the definition of oxidation and reduction in electrochemistry. Oxidation is the loss of electrons, while reduction is the gain of electrons. Therefore, since the cathode is where reduction takes place, the process is essential for the cell's operation, as it allows for the flow of current and the overall conversion of chemical energy to electrical energy.

The other choices do not accurately describe what occurs at the cathode. Oxidation occurs at the anode, electrons flow from the anode to the cathode rather than to the anode, and while voltage is indeed relevant in the context of electrochemical cells, absorption of voltage is not an accurate description of the processes occurring at the cathode.