Now, electrolytic cells are electrochemical cells that are supplied with an outside source of electrons, which allows reactant favorite redox reactions to occur. Now, recall that voltaic cells convert chemical energy into electrical work via the process of moving electrons in a spontaneous product favorite reaction. So, unlike voltaic cells, electrolytic cells do the opposite. They use up electrical work to power reactant favorite non spontaneous reactions. Now, let's look at an example. Let's look at the decomposition of molten sodium chloride.