If copper metal is added to a solution of an acid, the reaction would not occur spontaneously. Go to top . C. Equilibrium Understandings and Fundamental Concepts Equilibrium is attained in chemical cells when the voltage measured is equal to zero. As a reaction proceeds, these concentrations change and the measured value falls off until at equilibrium the measured voltage is equal to zero. Go to top .
Commercial batteries are examples of chemical cells.
Go to top . Electrolytic Cell Reactions Understandings and Fundamental Concepts Supplementary Information Electrolysis of water, electrolysis of concentrated brine, and electrolysis of molten salts are examples of the use of an electric current to produce a chemical reaction. For the purpose of the Regents examination, the definitions as stated in this section must be used. Go to top . The electrode at which reduction occurs in a cell is called a cathode.