Finish by balancing charge by adding electrons. The equation must again be simplified by canceling like terms on both sides of the equation. The energy released in a spontaneous redox reaction may be used to perform electrical work. Voltaic or galvanic cells Voltaic cells utilize spontaneous reactions. Reduction takes place at the cathode .
Cations move from anode to cathode.
Anions move from cathode to anode. The electrons flow toward the cathode, where they are used in the reduction reaction. Electrons flow from the anode to the cathode. Therefore, the anode is negative and the cathode is positive. Anions and cations move through a porous barrier or salt bridge.