Final answer:
Anode and cathode half cells are parts of a galvanic cell where oxidation and reduction occur, respectively. The anode is the negative electrode; the cathode is positive. Electric potential is measured relative to the standard hydrogen electrode.
Step-by-step explanation:
In electrochemistry, an anode half cell is where oxidation occurs, and a cathode half cell is where reduction takes place. Together, these half-cells form the electrodes of an electrochemical or galvanic cell. In a typical cell diagram, the anode is listed on the left and is considered the negative electrode as it donates electrons. Conversely, the cathode is the positive electrode and is listed on the right side of the cell diagram because it accepts electrons.
The electrodes in each half-cell reaction are represented by their chemical formulas, and interfaces between different phases are indicated by vertical lines. If a phase contains multiple substances, their formulas are separated by commas. A salt bridge maintains charge balance as electrons flow from the anode to the cathode through an external circuit during the cell's operation.
Electric potential of each half-cell is calculated using the equation Ecell = Ecathode - Eanode, reflecting the driving force of the redox reaction. The standard cell potential is determined under standard-state conditions and with reference to the standard hydrogen electrode (SHE), which is assigned an electric potential of 0 V.