What is the function of the negative electrode in a cell?

The function of the negative electrode, commonly referred to as the anode in a battery or electrochemical cell, is indeed to facilitate oxidation reactions. During these reactions, electrons are released, which allows them to flow towards the positive electrode. As oxidation occurs at the negative electrode, it creates a surplus of electrons, which are then available to move through the external circuit and provide electrical energy to any connected devices.

The other options, though relevant in the context of electrochemical cells, do not accurately describe the primary role of the negative electrode. While providing a pathway for current flow is essential for the entire circuit operation, it is not a specific function attributed to the negative electrode itself. The conversion of chemical energy into electrical energy happens as a broader process, involving both electrodes; therefore, it doesn’t pinpoint the negative electrode's unique contribution. Lastly, storing excess energy produced is typically related to batteries' overall design, particularly in capacitors or specific storage mechanisms, rather than a direct function of the negative electrode in an electrochemical reaction.