Galvanic or voltaic cell

In galvanic or voltaic cells, electricity is generated through the use of spontaneous chemical reactions.

A galvanic (or voltaic) cell is made of two half cells. Each half cell consists of a metal strip immersed in a solution of its own ions of known concentration — for example, a strip of zinc metal immersed in a 1 M aqueous solution of zinc ions forms a half cell.

Two metal plates and the solutions of their ions with known concentrations are thus required for the construction of a galvanic (voltaic) cell. The two half cells are constructed by immersing the two metal plates in solutions of their respective ions placed in separate containers, and are then combined to form the galvanic cell. The metal plates, called electrodes, are connected through a voltmeter by a conducting wire for the transfer of electrons between them. To complete the circuit, the two solutions are conn …