Electrolysis

Water Molecules Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 8

The decomposition of two water molecules. Diatomic Diatomic oxygen molecule hydrogen molecules + Electric current 2 H2O  O2 + 2 H2

Electrolysis H2O(l) O2 (g) + 2 H2 (g) “electro” = electricity Water Hydrogen gas forms Oxygen Electrode Source of direct current Electrolysis “electro” = electricity “lysis” = to split *H1+ H2O(l) O2 (g) + 2 H2 (g) water oxygen hydrogen This demonstration needs to be done using DC current (to produce a 2:1 H:O ratio). Use of AC current will produce equal amounts of hydrogen and oxygen gas. *Must add acid catalyst to conduct electricity Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 32

Electrolysis of Water Half reaction at the cathode (reduction): 4 H2O + 4 e -  2 H2 + 4 OH 1- Half reaction at the anode (oxidation): 2 H2O  O2 + 4 H 1+ + 4 e -