Redox Reactions - Electrode Processes

Electrode processes involve the transfer of electrons at the interface between an electrolyte and an electrode. Oxidation occurs at the Anode, while reduction occurs at the Cathode ($AN\ OX$ and $RED\ CAT$).

In a Galvanic (Voltaic) Cell, chemical energy is converted into electrical energy through spontaneous redox reactions. The anode is negative ($-$) and the cathode is positive ($+$).

The Standard Electrode Potential ($E^\circ$) is the potential developed when a metal electrode is in contact with a $1\ M$ solution of its own ions at $298\ K$ and $1\ bar$ pressure.

The Standard Hydrogen Electrode (SHE) serves as the reference electrode with an assigned potential of $0.00\ V$. It is represented as $Pt(s) | H_2(g, 1\ bar) | H^+(aq, 1\ M)$.

The Electrochemical Series is an arrangement of electrodes in increasing order of their standard reduction potentials. A lower (more negative) $E^\circ$ indicates a stronger reducing agent, while a higher (more positive) $E^\circ$ indicates a stronger oxidizing agent.

A Salt Bridge is a $U$-shaped tube containing an inert electrolyte like $KCl$ or $KNO_3$ in agar-agar. It completes the circuit and maintains electrical neutrality in the half-cells by allowing ion migration.

The feasibility of a redox reaction can be predicted using $E^\circ_{cell}$. If $E^\circ_{cell} > 0$, the reaction is spontaneous.