A galvanic cell, also known as a voltaic cell, is a type of electrochemical cell that converts stored chemical energy into electrical energy through spontaneous reactions. It consists of two electrodes: the anode and the cathode. The anode is the negatively charged electrode where oxidation occurs, characterized by the loss of electrons. Conversely, the cathode is the positively charged electrode where reduction takes place, involving the gain of electrons.
In a typical galvanic cell setup, the anode might be made of zinc, while the cathode could be composed of copper. As the reaction proceeds, electrons flow from the anode to the cathode, creating an electric current. This flow of electrons is essential for generating electricity, which can be measured using a voltmeter, a device that quantifies the electrical output of the cell.
To maintain the flow of charge and complete the circuit, a salt bridge is employed. This component connects the two half-cells and allows for the movement of neutral ions, which are ions that do not exhibit acidic or basic properties. In the salt bridge, negatively charged ions, such as bromide, move towards the anode, while positively charged ions, like sodium, migrate towards the cathode. This movement of ions is crucial for balancing the charge as electrons travel through the external circuit, ensuring the galvanic cell operates efficiently.
Overall, the galvanic cell exemplifies the principles of electrochemistry, showcasing how chemical reactions can be harnessed to produce electrical energy, with oxidation and reduction processes playing pivotal roles in its functionality.