Of the following statements concerning electrochemical cells, the correct ones are: (a) The cathode is the negative electrode in both voltaic and electrolytic cells. (b) The function of a salt bridge is to permit the migration of electrons between the half-cell compartments of an electrochemical cell. (c) The anode is the negative electrode in a voltaic cell. (d) Electrons leave the cell from either the cathode or the anode, depending on what electrodes are used. (e) Reduction occurs at the cathode in both voltaic and electrolytic cells. (f) If electric current is drawn from a voltaic cell long enough, the cell becomes an electrolytic cell. (g) The cell reaction is an oxidationreduction reaction.

Understanding the differences between voltaic (galvanic) and electrolytic cells is crucial for mastering electrochemistry. Voltaic cells convert chemical energy into electrical energy using spontaneous redox reactions. They are the basis for batteries, where the chemical reaction creates a flow of electrons from the anode to the cathode through an external circuit.

Electrolytic cells, on the other hand, require an external source of electricity to induce non-spontaneous chemical reactions. This process is commonly used in electroplating, where a metal is deposited onto an electrode. The key distinction lies in their operating principles: voltaic cells harness spontaneous reactions, while electrolytic cells drive non-spontaneous reactions with external power.

They share similar setups with two electrodes, an electrolyte solution, and sometimes a salt bridge to maintain charge balance by allowing ions, not electrons, to move between compartments. It's important to remember that electrons never physically pass through the salt bridge.

In electrochemical cells, electrodes play vital roles and are known as the cathode and anode. The anode is where oxidation occurs; it loses electrons. Conversely, at the cathode, reduction takes place as it gains electrons.

Determining whether an electrode is positive or negative depends on the cell type. In a voltaic cell, the anode is negative since the cell works based on spontaneous reactions, pushing electrons out of the anode through the circuit. The cathode is positive, accepting these electrons to complete the circuit. However, this polarity is reversed in an electrolytic cell because external energy is provided to drive the reactions. Here the cathode is negative, receiving electrons from the external source, while the anode is positive. Keeping these distinctions clear is essential for understanding the flow of electrons and the functioning of electrochemical cells.

Redox reactions are at the heart of electrochemical cells. These reactions involve the transfer of electrons between chemical species. When a substance loses electrons, we term it oxidation; when it gains electrons, it's called reduction.

These reactions are coupled—whenever one species is oxidized, another is simultaneously reduced. This electron transfer process is what drives the current in voltaic cells and is forced by an external power source in electrolytic cells. An easy way to remember the distinction is the mnemonic 'OIL RIG': Oxidation Is Loss, Reduction Is Gain.

In voltaic cells, the spontaneous redox reaction generates electric current, while in electrolytic cells, the applied current induces a redox reaction. Both types of cells are fundamental in various technologies, from powering portable electronics to synthesizing valuable chemicals.